The original method is introduced by PRL 82,2713(1999) 本文为本人工作记录。程序下载及计算方法请到 https://sourceforge.net/projects/ideal-strength-vasp/?source=navbar 感谢本程序作者： Dr. Hanyu Liu Email: hanyuliu801@gmail.com 准备工作 1.结构优化。将CONTCAR到出，在MS中导入对称性， 再转为POSCAR（for further calculations） 2.编译VASP。把VASP安装包cp到自己的目录。 for ideal tensile strength, add 'FCELL(1,1)= 0.0' to constr_cell_relax.F of vasp code. #the Stress at x axis is fixed and vasp not relax the lattice at x axis. for ideal shear strength, add 'FCELL(1,3)= 0.0' and 'FCELL(3,1) = 0.0' constr_cell_relax.F of vasp code. Here, you need to recompile vasp. 【make clean 】【make】 我在make的过程除了error： 没有lib。Lib文件放在mu'lu中，改下路径ming ，OK！ 输入文件 0. pbs.sh (集群上提交任务的脚本 ./strenth4.py Strength.log) 1.POSCAR 2. POTCAR 3. KPOINTS (不用太大： ./writekp.py 0.04) 4. strength4.py (核心程序，下载到Hanyu主页，见文章开篇) 5. input.dat (strength4.py 要读的输入文件) as followed: POSCAR #the name of POSCAR 0.02 #strain of distortion 100 #total step of distortion (虽说一般30steps即可，建议设置大一些，因为数据够了的话可以手动kill job) -45.0 35.264390 0.0 # rotate Z, Y and X. 1 # 1 tensile, 2 shear /home/zzu002/lhy/test/vasp/vasp.5.3-1/vasp # 提任务的命令。注意tensile和shear 的vasp路径不同！ 关于计算的方向： We set x axis as tensile strength direction (tensile (x)). Also we set x and z axis as shear direction (shear (x) ). For example, if you want to calculating ideal strength of Diamond along 100, you just set 0.0 0.0 0.0. If you want to calculate 110 orientation, you need set -45.0 0.0 0.0 If you want to calculate 111 orientation, you need set -45.0 35.264390 0.0. It is for rotating the x, y and z axis as a Right-handed helical rule. 我计算的tensile plane： TENSILE dire input#rotate Z, Y, X. GPa jobID jobState 100 0.0 0.0 0.0 103.115345 53421 killed 110 -45.0 0.0 0.0 100.23066 53422 killed 111 -45.0 35.264390 0.0 120.147138 53463 killed 001 0.0 90.0 0.0 75.300806 53464 killed 010 -90.0 0.0 0.0 122.560777 53465 killed 101 0.0 45.0 0.0 75.7 54584 011 -90.0 45.0 0.0 64 54585 +101 0.0 -45.0 0.0 82 54586 +110 45.0 0.0 0.0 54587 =110 killed 11+1 -45.0 -35.26439 0.0 10.961293 54953 SHEAR-001 1 0.0 90.0 0.0 55035 2 0.0 90.0 90.0 55036 3 0.0 90.0 180.0 55161 Research highlights: 1, Miao Zhang, Mingchun Lu, Yonghui Du, Lili Gao, Cheng Lu and Hanyu Liu, Hardness of FeB4?: Density functional theory investigation J. Chem. Phys., 140, 174505 (2014) 2, Yinwei Li, Jian Hao, Hanyu Liu, Siyu Lu and John S. Tse High energy density and superhard nitrogen-rich B-N compounds, Phys. Rev. Lett., 115, 105502 (2015) 3, Miao Zhang, Hanyu Liu, Quan Li, Bo Gao, Yanchao Wang, Hongdong Li, Changfeng Chen and Yanming Ma, “Superhard BC3 in cubic diamond structure” Phys. Rev. Lett., 114, 015502 (2015) 4, Quan Li, Hanyu Liu, Dan Zhou, Weitao Zheng, Zhijian Wu and Yanming Ma, novel low compressible and superhard carbon nitride: Body-centered tetragonal CN2 Phys. Chem. Chem. Phys., 14, 13081–13087 (2012)
1) oscillator strength In spectroscopy, oscillator strength is a dimensionless quantity that expresses the probability of absorption or emission of electromagnetic radiation in transitions between energy levels of an atom or molecule. 2) Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation . It is a form of luminescence . In most cases, the emitted light has a longer wavelength , and therefore lower energy, than the absorbed radiation. The most striking example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the spectrum , and thus invisible to the human eye, while the emitted light is in the visible region, which gives the fluorescent substance a distinct color that can only be seen when exposed to UV light . Fluorescent materials cease to glow immediately when the radiation source stops, unlike phosphorescence , where it continues to emit light for some time after. 3) Quantum yield can also be defined for other events, such as fluorescence : {\displaystyle \Phi ={\frac {\rm {\#\ photons\ emitted}}{\rm {\#\ photons\ absorbed}}}} Here, quantum yield is the emission efficiency of a given fluorophore .
http://en.wikipedia.org/wiki/Ultimate_tensile_strength Ultimate tensile strength From Wikipedia, the free encyclopedia Ultimate tensile strength ( UTS ), often shortened to tensile strength ( TS ) or ultimate strength , is the maximum stress that a material can withstand while being stretched or pulled before failing or breaking. Tensile strength is the opposite of compressive strength and the values can be quite different. Some materials will break sharply, without deforming, in what is called a brittle failure . Others, which are more ductile , including most metals, will stretch some - and for rods or bars, shrink or neck at the point of maximum stress as that area is stretched out. The UTS is usually found by performing a tensile test and recording the stress versus strain ; the highest point of the stress-strain curve is the UTS. It is an intensive property ; therefore its value does not depend on the size of the test specimen. However, it is dependent on other factors, such as the preparation of the specimen, the presence or otherwise of surface defects, and the temperature of the test environment and material. Tensile strengths are rarely used in the design of ductile members, but they are important in brittle members. They are tabulated for common materials such as alloys , composite materials , ceramics , plastics , and wood . Tensile strength is defined as a stress, which is measured as force per unit area . For some non-homogeneous materials (or for assembled components) it can be reported just as a force or as a force per unit width. In the SI system , the unit is the pascal (Pa) (or a multiple thereof, often megapascals (MPa), using the mega- prefix); or, equivalently to pascals, newtons per square metre (N/m2). The customary unit is pounds-force per square inch (lbf/in2 or psi), or kilo-pounds per square inch (ksi, or sometimes kpsi), which is equal to 1000 psi; kilo-pounds per square inch are commonly used for convenience when measuring tensile strengths. Contents 1 Concept 1.1 Ductile materials 2 Testing 3 Typical tensile strengths 4 See also 5 References 6 Further reading Concept Ductile materials Stress vs. Strain curve typical of aluminum 1. Ultimate strength 2. Yield strength 3. Proportional limit stress 4. Fracture 5. Offset strain (typically 0.2%) Stress vs. strain curve typical of structural steel 1. Ultimate strength 2. Yield strength 3. Fracture 4. Strain hardening region 5. Necking region A: Engineering stress B: True stress Many materials display linear elastic behavior, defined by a linear stress-strain relationship, as shown in the figure up to point 2, in which deformations are completely recoverable upon removal of the load; that is, a specimen loaded elastically in tension will elongate, but will return to its original shape and size when unloaded. Beyond this linear region, for ductile materials, such as steel, deformations are plastic . A plastically deformed specimen will not return to its original size and shape when unloaded. Note that there will be elastic recovery of a portion of the deformation. For many applications, plastic deformation is unacceptable, and is used as the design limitation. After the yield point, ductile metals will undergo a period of strain hardening, in which the stress increases again with increasing strain, and they begin to neck , as the cross-sectional area of the specimen decreases due to plastic flow. In a sufficiently ductile material, when necking becomes substantial, it causes a reversal of the engineering stress-strain curve (curve A); this is because the engineering stress is calculated assuming the original cross-sectional area before necking. The reversal point is the maximum stress on the engineering stress-strain curve, and the engineering stress coordinate of this point is the tensile ultimate strength, given by point 1. The UTS is not used in the design of ductile static members because design practices dictate the use of the yield stress . It is, however, used for quality control, because of the ease of testing. It is also used to roughly determine material types for unknown samples. The UTS is a common engineering parameter when designing brittle members, because there is no yield point . Testing Round bar tensile specimen after testing Main article: Tensile testing Typically, the testing involves taking a small sample with a fixed cross-section area, and then pulling it with a controlled, gradually increasing force until the sample changes shape or breaks. When testing metals, indentation hardness correlates linearly with tensile strength. This important relation permits economically important nondestructive testing of bulk metal deliveries with lightweight, even portable equipment, such as hand-held Rockwell hardness testers. It should be noted that while most metal forms, like sheet, bar, tube and wire can exhibit the test UTS, fibers, such as carbon fibers, being only 2/10,000th of an inch in diameter, must be made into composites to create useful real-world forms. As the datasheet on T1000G below indicates, while the UTS of the fiber is very high at 6,370MPa, the UTS of a derived composite is 3,040MPa - less than half the strength of the fiber. Typical tensile strengths Typical tensile strengths of some materials Material Yield strength (MPa) Ultimate strength (MPa) Density (g/cm3) Structural steel ASTM A36 steel 250 400 7.8 Mild steel 1090 248 841 7.58 Human skin 15 20 2.2 Micro-Melt® 10 Tough Treated Tool Steel (AISI A11) 5171 5205 7.45 2800 Maraging steel 2617 2693 8.00 AerMet 340 2160 2430 7.86 Sandvik Sanicro 36Mo logging cable Precision Wire 1758 2070 8.00 AISI 4130 Steel, water quenched 855°C (1570°F), 480°C (900°F) temper 951 1110 7.85 Titanium 11 (Ti-6Al-2Sn-1.5Zr-1Mo-0.35Bi-0.1Si), Aged 940 1040 4.50 Steel, API 5L X65 448 531 7.8 Steel, high strength alloy ASTM A514 690 760 7.8 High-density polyethylene (HDPE) 26-33 37 0.95 Polypropylene 12-43 19.7-80 0.91 Stainless steel AISI 302 - Cold-rolled 520 860 8.19 Cast iron 4.5% C, ASTM A-48 130 200 Liquidmetal alloy 1723 550-1600 6.1 Beryllium 99.9% Be 345 448 1.84 Aluminium alloy 2014-T6 414 483 2.8 Polyester resin (unreinforced) 55 Polyester and Chopped Strand Mat Laminate 30% E-glass 100 S-Glass Epoxy composite 2358 Aluminium alloy 6063-T6 248 2.63 Copper 99.9% Cu 70 220 8.92 Cupronickel 10% Ni, 1.6% Fe, 1% Mn, balance Cu 130 350 8.94 Brass 200 + 550 5.3 Tungsten 1510 19.25 Glass 33 2.53 E-Glass N/A 1500 for laminates, 3450 for fibers alone 2.57 S-Glass N/A 4710 2.48 Basalt fiber N/A 4840 2.7 Marble N/A 15 Concrete N/A 3 2.7 Carbon fiber N/A 1600 for Laminate, 4137 for fiber alone 1.75 Carbon fiber (Toray T1000G) 6370 fibre alone 1.80 Human hair 380 Bamboo 350-500 0.4 Spider silk (See note below) 1000 1.3 Darwin's bark spider silk 1652 Silkworm silk 500 1.3 Aramid ( Kevlar or Twaron ) 3620 3757 1.44 UHMWPE 24 52 0.97 UHMWPE fibers (Dyneema or Spectra) 2300-3500 0.97 Vectran 2850-3340 Polybenzoxazole (Zylon) 2700 1.56 Pine wood (parallel to grain) 40 Bone (limb) 104-121 130 1.6 Nylon , type 6/6 45 75 1.15 Epoxy adhesive - 12 - 30 - Rubber - 15 Boron N/A 3100 2.46 Silicon , monocrystalline (m-Si) N/A 7000 2.33 Silicon carbide (SiC) N/A 3440 Ultra-pure silica glass fiber-optic strands 4100 Sapphire (Al 2 O 3 ) 400 at 25*C, 275 at 500*C, 345 at 1000*C 1900 3.9-4.1 Boron Nitride Nanotube N/A 33000 ? Diamond 1600 2800 3.5 Graphene N/A 130000 1.0 First carbon nanotube ropes ? 3600 1.3 Colossal carbon tube N/A 7000 0.116 Carbon nanotube (see note below) N/A 11000-63000 0.037-1.34 Carbon nanotube composites N/A 1200 N/A Iron (pure mono-crystal) 3 7.874 ^a Many of the values depend on manufacturing process and purity/composition. ^b Multiwalled carbon nanotubes have the highest tensile strength of any material yet measured, with labs producing them at a tensile strength of 63 GPa, still well below their theoretical limit of 300 GPa . The first nanotube ropes (20mm in length) whose tensile strength was published (in 2000) had a strength of 3.6 GPa. The density depends on the manufacturing method, and the lowest value is 0.037 or 0.55 (solid). ^c The strength of spider silk is highly variable. It depends on many factors including kind of silk (Every spider can produce several for sundry purposes.), species, age of silk, temperature, humidity, swiftness at which stress is applied during testing, length stress is applied, and way the silk is gathered (forced silking or natural spinning). The value shown in the table, 1000 MPa, is roughly representative of the results from a few studies involving several different species of spider however specific results varied greatly. ^d Human hair strength varies by ethnicity and chemical treatments. Typical properties for annealed elements Element Young's modulus (GPa) Offset or yield strength (MPa) Ultimate strength (MPa) silicon 107 5000–9000 tungsten 411 550 550–620 iron 211 80–100 350 titanium 120 100–225 240–370 copper 130 33 210 tantalum 186 180 200 tin 47 9–14 15–200 zinc (wrought) 105 110–200 nickel 170 14–35 140–195 silver 83 170 gold 79 100 aluminium 70 15–20 40-50 lead 16 12 See also Flexural strength Strength of materials Tensile structure Toughness References ^ Degarmo, Black Kohser 2003 , p. 31 ^ Smith Hashemi 2006 , p. 223 ^ a b NDT-ed.org ^ E.J. Pavlina and C.J. Van Tyne, Correlation of Yield Strength and Tensile Strength with Hardness for Steels , Journal of Materials Engineering and Performance , 17:6 (December 2008) ^ http://www.carbonfibertubeshop.com/tube%20properties.html ^ http://www.matweb.com/search/datasheet.aspx?matguid=638937fc52ca4683bc0c3f18f54f5a24 ^ http://www.matweb.com/search/DataSheet.aspx?MatGUID=de22e04486ff4598a26027abc48e6382 ^ http://www.matweb.com/search/DataSheet.aspx?MatGUID=64583c8ce6724989a11e1ef598d3273d ^ http://www.matweb.com/search/DataSheet.aspx?MatGUID=c140b20b165941c7a948e782eeced4ea ^ http://www.matweb.com/search/datasheet.aspx?MatGUID=722e053100354c02a6d450d5d7646d82 ^ http://www.matweb.com/search/DataSheet.aspx?MatGUID=b141bfe746f142638fdc30ac59aa306e ^ USStubular.com ^ Beryllium I-220H Grade 2 ^ Aluminum 2014-T6 ^ a b East Coast Fibreglass Supplies: Guide to Glass Reinforced Plastics ^ Tube Properties ^ Material Properties Data: Soda-Lime Glass ^ Basalt Continuous Fibers . Retrieved 2009-12-29 . ^ Toray Properties Document ^ I Agnarsson, M Kuntner, T A Blackledge, Bioprospecting Finds the Toughest Biological Material: Extraordinary Silk from a Giant Riverine Orb Spider ^ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2716092/table/T3/ ^ Tensile and creep properties of ultra high molecular weight PE fibres ^ Mechanical Properties Data ^ Zylon Properties Document ^ Uhu endfest 300 epoxy: Strength over setting temperature ^ Fols.org ^ Lee, C. et al. (2008). Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene . Science 321 (5887): 385. Bibcode : 2008Sci...321..385L . doi : 10.1126/science.1157996 . PMID 18635798 . Lay summary . ^ IOP.org Z. Wang, P. Ciselli and T. Peijs, Nanotechnology 18, 455709, 2007. ^ Yu, Min-Feng; Lourie, O; Dyer, MJ; Moloni, K; Kelly, TF; Ruoff, RS (2000). Strength and Breaking Mechanism of Multiwalled Carbon Nanotubes Under Tensile Load. Science 287 (5453): 637–640. Bibcode : 2000Sci...287..637Y . doi : 10.1126/science.287.5453.637 . PMID 10649994 . ^ F. Li, H. M. Cheng, S. Bai, G. Su, and M. S. Dresselhaus, Tensile strength of single-walled carbon nanotubes directly measured from their macroscopic ropes . doi : 10.1063/1.1324984 ^ K.Hata. From Highly Efficient Impurity-Free CNT Synthesis to DWNT forests, CNTsolids and Super-Capacitors (PDF). ^ Elices, et al.. Finding Inspiration in Argiope Trifasciata Spider Silk Fibers . JOM . Retrieved 2009-01-23 . ^ Blackledge, et al.. Quasistatic and continuous dynamic characterization of the mechanical properties of silk from the cobweb of the black widow spider Latrodectus hesperus . The Company of Biologists . Retrieved 2009-01-23 . ^ A.M. Howatson, P.G. Lund, and J.D. Todd, Engineering Tables and Data , p. 41 Further reading Giancoli, Douglas, Physics for Scientists Engineers Third Edition (2000). Upper Saddle River: Prentice Hall. Köhler, T., Vollrath, F. (1995). Thread biomechanics in the two orb-weaving spiders Araneus diadematus (Araneae, Araneidae) and Uloboris walckenaerius (Araneae, Uloboridae). Journal of Experimental Zoology 271 : 1–17. doi : 10.1002/jez.1402710102 . T Follett, Life without metals Min-Feng, Yu, Lourie, O, Dyer, MJ, Moloni, K, Kelly, TF, Ruoff, RS (2000). Strength and Breaking Mechanism of Multiwalled Carbon Nanotubes Under Tensile Load. Science 287 (5453): 637–640. Bibcode : 2000Sci...287..637Y . doi : 10.1126/science.287.5453.637 . PMID 10649994 . George E. Dieter, Mechanical Metallurgy (1988). McGraw-Hill, UK
转自: http://emuch.net/html/201105/3213111.html 作者: gavinliu7390 (站内联系TA) 收录: 2011-05-27 发布: 2011-05-20 http://code.google.com/p/ideal-strength-vasp/downloads/list Recently, I write a python script to calculate ideal strength of crystal combination with VASP. You can download it from above website. the details is found from readme in wiki at that website. Introduction About method details, please see PRL 82,2713(1999) Details First you need to modify vasp code. If you want to calculate ideal tensile strength, you should add 'FCELL(1,1)=0.0' to constr_cell_relax.F of vasp code. And if you choose ideal shear strength, you should add 'FCELL(1,3)= 0.0' and 'FCELL(3,1) = 0.0' to constr_cell_relax.F of vasp code. Here, you need to recompile vasp. second, you should prepare input.dat and this file as below: POSCAR 0.02 #strain 20 #step -45.0 -35.264390 0.0 # rotate Z, Y and X. 1 # 1 tensile, 2 shear mpiexec -np 8 vasp.4.6 The first line is the name of POSCAR. The second line is strain of distortion. The third line is total step of distortion. The fourth line is degree of rotation. This is for calculating special orientation. For example, if you want to calculating ideal strength of Diamond along 100, you just set 0.0 0.0 0.0. If you want to calculate 110 orientation, you need set -45.0 0.0 0.0. If you want to calculate 111 orientation, you need set -45.0 -35.264390 0.0. The five line is to choose tensile of shear. The sixth line is execute command.
关于（2012年个人日志始终篇） 题记 ：关于很多事情，我的个人态度或许依然过于理想化。作为小人物，本日志将剖析反思自我，五年之内或以此为鉴，或以此玩味渐变之妙趣。本文或五年后再续。 关于 理想化人生 ： 但愿人生莫短莫长，世间皆是好人，好人幸福平安。 关于 亲情 ： 有一 天，若我有一个孩子，我希望 ta 有机会幸福地向同学炫耀和我自由地坦露心声是件多么轻松和快乐的事情，我希望 ta 能认为我带 ta 全家旅游和去帮助别人分别是人活着从自然属性和社会属性看最有意义的事情。我希望 ta 能理解我为何要把最好吃的东西让小小的 ta 亲自给 ta 的爷爷奶奶送去。我希望 ta 能更多地看到 ta 的亲戚都是多么的团结，多么的温馨。 关于 友情 ： 想起和老同学的快乐聚餐，想起军训结束好久了，诸友一起坐车时仍共唱《军中绿花》的情形，想起和好友黑夜闲游深山的那种兴奋情愫。这慢慢引导我有一个关于友情的梦想。但愿这样的日子会多起来：忙时共勉激情奋斗，闲时一起品茗散心，偶尔三杯淡酒下肚，畅谈天下趣闻。地理距离可有，心里距离恒无。不必月月联系，不必常常牵挂，一旦急切呼唤，诸友皆聚身边。没有束缚，没有孤独。没有尖酸，没有怀疑。没有隔膜，没有背叛。不必涌泉相报，绝不以怨报德。即使时过境迁，即使沧海桑田，我们仍都有这种感觉：彼此相遇相识真的是一种幸运。 中国将永远和平的梦想是美好的，但现实未必是如此，当伤害对方成为一种民族生存的必需时，身为男儿，无论那时我多么沧老文弱，一旦我有机会，我绝不会放弃武力和智慧进行彻底地抗争！这时我身边的朋友，志同与否不再重要，若能道合齐心杀敌也算一种幸福的默契。换而言之，这时的朋友若能像抗战某段时期的国共，我也会莫大的欣慰。如果我为此死了，我希望我身边健在的朋友认为：这死亡不再是一种虚伪，认识我至少也不是一种错。 关于 爱情 ： Love is a paradox, so I have no special words to share. Here, I wish everyone could own the love as “Hold on his/her hands tightly, and be old together with him/her,and never give up”. 关于 中国教育 ： 我也不想多说，因为大家都是过来人，都是明白人，都有自己几乎根深蒂固的观点。好多好多年前，我有过美好的期盼，如今却不再做个愤青，去期盼去评判，不是消极，而是先要快乐地面对事实，先做好自己。分享一下自己的一篇私密日记吧。 今天（ 2011 ， 01,17 ）大考刚归来，喜忧却参半。有摆脱长期紧张压抑疲惫的兴奋，有担心考后一切事物情况的未知。现在是晚上，躺在床上，我第一次睡了下铺，伴随室友的笑谈，盯着上铺的床板，突然有身心俱碎的疲劳。学校的床板是薄木做的，却坚强地送走了一届又一届的学生，没有断裂，砸伤下面的学生。我大四临近毕业，为考研平时外住，今天就睡一晚，我想最终也不会被砸到吧？我眼睛盯着床板，疲劳唤来睡意，不经意间，本能的落下单行泪来，习惯了这种被唤睡的方式。然而在这今天的薄板下，却百感交集，更多的是酸楚猖狂。 是啊！中国的教 育制度成就一批 人才，却最终没有培育出一个真正诺贝尔来， 10 多年考试换回更多的思维模式。模板最成功的地方，是它塑造的更为压抑本能的所谓优秀的学生。我问了一些优秀学生，你的爱好是什么？多是无从回答，或是被遗失在落尘的角落，成了心灵寄托：如果有一天有时间有自由，我一定会拾起它。可是现实总不给他们机会，升学 - 就业 - 生活，忙忙碌碌所谓的优秀的模板，一个个更多忽略自己而茫然不知或者不知所措的模板。于是终于一代代遗传着这种吞噬某些精神的瘟疫，中国的教育改革仍是金玉其外的危房。与现实脱节的教育，造就更多的社会矛盾。在学校优秀者在中国的社会上游刃有余者却是少数，腰缠万贯的更多的是爆发户，是商人。为了自己利益而处心积虑地伤人，被教育扭曲了本性地对教育报复，于是中国造就的多是自诩企业家的商人，少是为社会分忧企业家。业内公认的是：在中国，先做企业家，必然成不了的企业家；必须先做商人，再有这个打算。我读到后，曾几度为当代中国教育鸣悲：为何总是在中国产生这样的怪胎思想？为打造中国文化软实力，中国不惜亿金在国外推广孔子学院，却也得到了欢迎（至少这是国内的报道结果），或许因为它遵循国外的教育模式，严格地讲：外国自由的成功教育制度，是吸收了我国几千年前孔子年代的思想！ 我盯着这块薄薄的床板，这块通过某些唯心主义的东西给我太多压抑的床板。它最终要塌落下来，然而在它塌落前却还是压坏一批人。使这批人蚕食童性，蚕食真正的爱情，蚕食爱好，蚕食动手能力，蚕食社交能力等等，最终与现实脱节，它却利用浮夸学位的手段满足他们的虚荣，使更多人乐于盲目掉入这种陷阱，忽略了很多人生的幸福，了此一生，茫然不知，循环往复 … 关于 老人 ： 每次我看到那些生活质量很高的老人，脑海里总浮出，他年轻时是多么的辛苦与操劳，或者他的祖上曾经是多么地艰辛，无奈和痛楚，一定遭受过物质或者精神的折磨的情景。每次我看到生活质量低下的老人，我总是想到，他与前者相比，确实凄惨，也许他年轻的时候因为无知而荒度，也许因为运气不佳而破落，我从没有去考虑他是否真的幸福，是否真的需要这个社会的帮助，一看到那些沉积着泥土的皱纹，我就自然而然地感觉这个社会为其做的还是不够的，特别是那些年轻已经有为和年老物质很是丰腴的人群，确实应该承担更多的人类责任，需要点心思去关注那些生活落魄的老人，因为，活着的时候，你无论多么光洁名耀，你终将要老去，埋入泥土，同样是生命，请对类似的生命，除种群和个体竞争外，再多一点点人性的同情。 每次看到受到大家爱戴的慈祥老人时，我总是悄悄地在心中替他幸福地乐啊乐啊，为什么呢？我那时总是暗暗地想到，他童年或者少年的时候，因为人类天性使然，正在做一些调皮捣蛋（若是大人做了就是不道德或者不合法的受多数人会指责的傻事）回忆版电影似的情景，这一对比，我就偷偷地在他面前自然地笑了，人嘛，哪能生来就是圣人，好人，完美的人，他已有一个安详的灵魂。而当我看到那些备受指责的老人时，我的心情就复杂了很多，哀其不幸啊！感慨其当年为何不早点清醒，感慨其在活着的时候，为何不赶紧醒过来，做一些亲朋好友多能认可的事情？殊不知浪子回头金不换，更何况对于一个行将就木的凄苦老人，再加上人性同情弱者的心理，也不至不能心静地安享晚年啊？！板桥老先生是说过“糊涂是老难得了”，但不能老糊涂啊。 关于 善恶 ： 善恶是相对的。这里的相对，既是意思的相反，也指其各自的定义是相对的。以善为例，道德的事就是善事，这是多数人可以接受的。可是，什么是道德的事呢？时代、文化和地域的差异，却导致不同的定义。所以善，不具备绝对的定义。凡物各事，总有一群既得利益者。当这群既得利益者广大，而定义某种事件的善的程度远大于恶时，那事就是那时那地的善事。方今世界村庄化，我认为，最大环境最大程度群众多能认可的事就是善事，符合人类的最优生存之道的事就是善事，比如和平。当然，自己不是搞这个方面的，只是没有思想桎梏，完全出于自己本性地胡乱定义，可以接受各家批评。但是自己却努力执着于做自己认为正确的事情。 除恶扬善，是个备受欢迎的词。这里的除恶是指他恶和己恶皆努力除之，而扬善则只为扬他善而非己善。拥有这个能力的人，无论存在多少误解，多少痛楚，终究往往得到多数人的尊重。至善若水，自然地往低处流，这里的低当然指代弱势群体。所以，出于同是生命的原因，请对他们尽量多点宽恕和关爱吧。对于善人的人生，还是请多给予推手，不从功利地肯定和鼓励来说，就是为了让这还是匮乏爱的世界，多些人去传递温暖。可是，“好人一生平安”却是大家的互相的祝愿词。因为，大家多想做个真好人，但都深知好人真是多难做。对恶人的铲除，是大快人心的事。除的恶人愈多，那人就愈近至善，愈是被人敬重，当然，某段日子里，某些道路上也越是艰难。这些是我们多为熟知的人情。可是，阻碍善事的人是恶人，近至恶，多被人忽略，甚至自己也因无知去盲从做过如此之人。因为，很多时候，那些善事降到自己身上的几率小于影响到自己的恶事。这也是人们被鼠灾蝗祸突袭时顿感惊讶的原因之一。 关于 虚伪 ： 虚伪，顾名思义，假的意思，真的对立面，很容易让人想起面具这个词。多数人被称作虚伪时，我想都不是有什么太好的感觉。因为大家多知道它是个贬义词，也是一个敏感词，因此大家多不敢也不想去触及。很多时候，很多亲友都告诫我：知人知面不知心。我渐渐晓得了。看到过逢场作戏的戏子型人格的人 , 他们不懂得自尊自爱 , 出卖人格尊严实现个人利益 , 为人所不耻。更有甚者，有些道貌岸然的伪君子，他们具有君子之身小人之心 , 全掩其不善而著其善 ，这是让人唾骂的，甚至有些连戏子型人格的人也鄙视这群伪君子：宁做自己的真小人，不做他们的伪君子！ 面具的消极作用是不言而喻的，过分的人格面具膨胀牺牲本身的天性而总生活在紧张之中，是要出乱子的。荣格先生曾提出人格面具理论。我不是搞心理学的，但读了一点，感觉有意思，觉得有必要分享。人格面具的形成是普遍必要的，与教育背景有着很大的关系，它保证了让我们与其他性格的人甚至不喜欢的人和睦相处以共赢惠及长远的发展，从存在即合理以及辩证法的观点也都可以佐证，只不过涉及度的问题。我们国内校园内的理论政治教育从小到大给我们灌输真实和坦诚等思想，这是好事。因为不如此的话，社会风气日下那是必然，国家更是难于管理和发展。当然，方今的校园外的行为道德教育如何，这里不做讨论。可是就说真诚和坦诚一定是好事吗？能读懂这篇文章的，都不是小孩子，都有各自的多彩的阅历，我想多能认同：善意的谎言，有时是一种感动；理性的法律制裁，也有让人扼腕痛惜的。就简单到，平日的交往，你真诚和直爽地不假思索地数落对方的不是，稍有不假造成的表达不到位，适当其反那是司空见惯的。当然志同道合性格形似的，可以减小这个频率，可是大环境和个性格多异性必然不能把这个概率降低到零。比如文革时期的“ 村骗乡、乡骗县 , 一直骗到国务院”，“ 说多少实话 , 挨多少臭骂 , 说多少谎 , 得多少奖”。 在这样一种道德氛围下 , 慢慢地一些原来、真诚坦荡的人道德潜能受到抑制 , 为了与社会适应、协调 , 他们不得不口是心非 , 变得虚伪，于是道德滑坡、 世风日下、人格危机 , 进而形成一种恶性循环。虽然方今整体风气没有如此明显，有“小月月门”，有“小月月再现门”，有感动中国人物，还是有感动中国人物，但风气真的如何，问媒体，乱哄哄的，有老牛部门的，有松鼠部门的，小马不得而知，估计元芳也不知所措。至于我们或处于象牙塔内，或处于底层，对此感觉还非成熟，甚至这个时代也只有盖棺定论的时候才算有些真实。 季羡林先生曾从能力的角度谈论过虚伪，他认为有时谦虚，过了度就是虚伪了。两者之间并非泾渭分明，简直可以说是因人而异，因地而异，因时而异，掌握一个正确的分寸难于上青天。而真诚是第一标准。不管东方或西方，必须出之以真诚。有意的过分的谦虚就等于虚伪。至于吹牛之流，则为东西方同样所不齿，不在话下。对于虚伪人格的度的衡量，我们各自忖度，适可而止，莫妄自定义他人或自己是否虚伪，日久见人心，借孔子判断别人是否虚伪的方法“听其言而观其行” ，我也造个孔子体：“扪己心而观己行。”防止有“错字”（官方说法为“通假字”）而错解东哥的意思，说东哥“虚伪”。天冷，我不想跳进黄河去洗，所以老老实实将此翻译成现代语：弱弱地问一下自己：“此事此景，我们内心深处是否善意真诚？”，然后为人行事。 关于 梦想 ： 我们很小的时候，被老师逼着写一篇这样的小学作文：《我的理想》。于是，大家集中精力，思考这个命题，虽然可能忘记当初写了什么内容，估计认真完成的，都对此事有些印象。因为那时候很小，见世面窄，不知道理想都包括那些，脑子里能浮现的就是书本上的介绍，科学家，医生，老师，工程师等简单的介绍，并不清楚他们的工作性质是什么，工作内容是什么，更别提自己是否真的喜欢那些职位，于是我们有些想当然地选择了某个作为理想写在作文里，也有些歪着小脑袋东瞅瞅西看看随大流选择了科学家，当然也有特殊情况的，比如亲友邻居有得病的或者被白求恩先生事迹感化的，那理想是当个医生；教师世家的，或许当个老师。可是，如今，长那么大了，我们多数并没有选择原来的理想，因为，等到我们选择专业的时候，或是因为不了解，或是因为家长推荐，或是随机调剂的。我们花了三年或者四年或更久去了解所学的专业，发现自己不喜欢的时候，已经到就业的时候，这期间很多人没有去思考自己的理想是什么，虽然有了了解的能力，但是已经没了了解的时间。因为要生存，要马上就业。于是有些人设法忘记理想，因为身边有各自压力只能让自己放弃；有些人没有勇气放弃所学，因为放弃意味着放弃优势；有些人干脆没了理想，因为已经适应市场需求拿到了令人羡慕的待遇。当然也有些人为理想定下了自己的路线，甚至固守这个路线来证实自己的坚毅的个性，坚毅是值得敬佩的，当然挫败也是不可避免的，因为世界上每个人并不是生下来就是为我们的理想而服务的，所以改变规划并不降低对理想忠诚度的问题。我们不断长大，不断成熟，不断了解自己的内心深处的渴求，这是改变理想原因的一个可能；社会的其他成员或特殊因素在拒绝我们的理想得到实现的同时，也给了我们一个另一个被迫改变理想的可能，那时候，不被急于悲愤，因为固步自封的人是抓不住上帝关上一扇门并给我们打开另一扇窗的机遇的。 我这里一直谈到理想，好像并没有涉及到梦想的观点。那么理想是什么？顾名思义，理智的梦想，就是说理想是梦想，但多多少少有理智的成分在里边。我本人和这个地球上的一大批人一样，是个理想主义者或者说完美主义者。可是我智商受限，在接受现实的同时，同时还是童心不死，有着射手座甚至说所有人类的共性：向往集体和谐和个人自由。很多人从小就对豪车好房绝对的崇拜，可是这些真的提不起我太多兴趣，有时有些羡慕，可是很快却归于平静。我还没有怀疑过自己将来的挣钱的能力，也许它的证明将来还有梦想的成分吧，或者换而言之，没经历风雨，也只是梦里想想的自负在作祟而已。我感兴趣的只是我来证明我存在的价值，我为这个世界做过什么而被认可，当然并不是纯粹证明自己如何如何高尚，也不是像陈光标同志一样高调炫耀。我是个普通的小人物，智商情商运商都不佳，也有着人性的种种弱点。但我不断坚持着摸索，虽然这个梦想有两次过被击得支离破碎，但很庆幸它不是破镜，仍然重圆。因为我相信它是好的，所以我多么希望每个人都能有这样一个梦想，快乐而自由地去证明自己定义的有意价值，当然这种价值的实现不危害到任何生命或者感情；我多么希望每个人都能慢慢体味到梦想实现的幸福过程并一直到死去的那一刻刚好完成。因为活着的时候，真的实现了，那就是理想了，也就是目标完成。于是我思维的操作者下发下个命令：机器同志，为了不让你拥有实现目标后的无聊和失落，请您再设法进行下一个理想完成任务。 以上这些都是纯粹的理想主义和个人主义甚至唯心主义的想法。如果一个待我不错的经历人情的老人，在我身边，一定会开导我：你这傻孩子也傻的太可爱了吧，你怎么能认为你对别人的祝愿和希望就是别人想要的呢？虽然你的出发点或者意图是好的，但还要尊重他人的想法和个性啊，也许他们会误解你的意思甚至很不愉快呢。做你自己认为正确的事情吧。他们的，他们自己去思考，他们自己去做主，他们自己去承受结果。 关于 本日志 ： 本计划此日志风格为杂文刻薄犀利式风格，但鉴于有未成年亲友可能看到，故用这种假成熟稳重口味体来表述。 over ^_^
There are only two seasons in NC（short for NanChang）. one is summer，the other is winter. and this time i would like to talk about summer.which i am suffering . it impresses me not only the hot weather. besides that， there are something else. what are they？ Changeable weather . it maybe sunny in the morning，raining in the afternoon，colding in the evening. you could experience different seasons in a day or even just some hours. you nerve got to know what is happening next and what is prepared for you. maybe you think it is a good day for going out. be careful about that. something bad are around the corner. never go out without fully prepared and planned. Long period . the summer of NC may start from may， end at october . it lasts more than six months. in fact，it kills the autumn. that is why we don't have autumn in NC. sometimes i would complaint about the long time. and wonder howlife here survival from long period of so hot wether. are they special？ Water shortless . i mean in my dormitory. water suppling is sometimes going wrong. during that time. i feelvery misery and how valuable the water is ，how hard our life is. and my daily life goes in a mess. the WC is dirty and full of bad smell. i can't take a comfortable bath and enjoy the colding feeling. i wake up a lot of times during the short night. i am sleepless. it is the nightmare of me. the biggest pain is not the death of your best loving， it is without water ！ To summer up . living in NC is not that easy aswe think，especially in the summer. those who are survivaling here is not onlyneed a strong heart. a good health. besides that ， we eagerly neednon-stopped suppling offresh water！
The Y-doped MgZnCa alloys with ultrahigh specific strength and good corrosion resistance in simulate body fluid J.F. Wang a , b , , , Y.Y. Wei a , b , S.F. Guo c , , , S. Huang a , b , X.E. Zhou a , b , F.S. Pan a a National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, PR China b College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China c School of Materials Science and Engineering, Southwest University, Chongqing 400715, PR China Abstract The microalloying effects of Y on the microstructure, mechanical properties and bio-corrosion resistances of Mg 69 Zn 27 Ca 4 (at.%) alloy were investigated by X-ray diffraction, compressive tests and electrochemical treatments, respectively. The Y-bearing Mg-Zn-Ca alloys were found to possess an ultrahigh compressive strength above 1000MPa as well as high specific strength of 3.44×10 5 Nmkg -1 . The enhanced mechanical properties can be attributed to the ductile dendrite phase, Mg 12 YZn, which is dispersed in the matrix with the Y addition. Furthermore, the Y-doped Mg-Zn-Ca alloys studied in this work have much better corrosion resistance than traditional ZK60 and pure Mg alloys in simulated body fluid (SBF) at 37°C, which could be good candidates to be used as biomedical materials http://dx.doi.org/10.1016/j.matlet.2012.04.130 http://www.sciencedirect.com/science/article/pii/S0167577X12006222?v=s5
Design of high strength Fe-(P, C)-based bulk metallic glasses with Nb addition Sheng-feng GUO a , , , Ye SHEN b Abstract Bulk metallic glass (BMG) rods Fe 71 Mo 5- x Nb x P 12 C 10 B 2 ( x =1, 2, 3, 4 and 5) with diameter of 1 or 2 mm were synthesized by copper mold casting. The effects of Nb substitution for Mo on the structure, thermal and mechanical properties of Fe 71 Mo 5- x Nb x P 12 C 10 B 2 alloys were studied by X-ray diffraction, differential scanning calorimetry and compressive testing. The results show that the substitution of Nb for Mo leads to a decreased glass forming ability, but with plasticity of 1.0%, the fracture strength of Fe 71 Mo 2 Nb 3 P 12 C 10 B 2 alloy increases up to 4.0 GPa. The improvement of the fracture strength is discussed in terms of the enhancement of atomic bonding nature and the favorite formation of a network-like structure due to the substitution of Nb for Mo. http://www.sciencedirect.com/science/article/pii/S1003632611610327
God will make a way where there seems to be no way He works in ways we cannot see He will make a way for me He be my guide hold me closely to his side with love and strength for each new day He will make a way,he will make a way by a roadway in the wilderness he will lead me and rivers in the desert will I see heaven and earth will fade but his word will still remain he will do something new today
Rodfisher Eastman FIFA sent many of the Chinese funs again into daydreams of something like victories in world football games. Beyond daydreams, Chinese can never win strength games, and football is primarily a strength game, with its players running all the time and all over the ground, like wild beasts, not only of wild forces, but also of wild glories. Chinese can never win football games. It is a truth generally acknowledged to the modern world that human beings evolved from lower mammal animals, apes or their like. From the lowest mammal to the most evolved human race, evolution occurred in somewhat a sequential way, and there was and is actually a sequence of evolution. The lowest mammal and the most evolved Chinese make the two extremes of the sequence of evolution; and between the two extremes, there were and are higher mammals, beings of the genus homo behind the species homo sapiens, and beings of the species homo sapiens behind the Chinese. The closer to the lowest extreme, the more physical affinities the beings have to the lowest; and the remoter from the lowest, the less physical affinities to the lowest. The body hairs of the beings of the species homo sapiens closer to the lowest extreme, for example, are longer, fatter, thicker and covering more areas, and those of the beings remoter are shorter, slimmer, thinner and covering less areas. And the closer to the lowest extreme, the better physical faculties the beings have; and the remoter from the lowest, the worse physical faculties the beings have. And, by the way, the closer to the lowest extreme, the worse mental faculties the beings have; and the remoter from the lowest, the better mental faculties the beings have. Lower mammals can eat raw crude plants, human beings closer to the lowest extreme of the evolution sequence can eat raw vegetables and half-cooked beefs, but raw and uncooked things can only bring stomach problems to the Chinese who has been taking well-cooked refined foods for thousands of years. Lower mammals have better digestion than higher ones. Lower mammals can run faster and longer than human beings and human beings closer to the lowest can run faster and longer than those remoter from the lowest. Lower mammals have better physical strength than higher ones. Actually raw crude foods, if well digested, bring more physical strength, wild physical strength. Chinese can never win strength games, because they are too much evolved and because too much evolution deprived them of wild physical strength necessary to strength games. The games that Chinese can win are games of art and wisdom. As an inevitable result of evolution, Chinese excel, not in physical faculties, but in mental faculties, not in physical forces, but in mental powers.
Yonghe Zhang ionocovalent theory applications (15) A Relation between Zhang Lewis AcidStrengths and Dopant Elements Marcel et al. established a relation between the Zhang Lewis acid strength of the dopant element and its scattering cross section ： LSn 4+ /LGe 4+ QGe 4+ /QSn 4+ : In fact, we have recently shown(2,3,4) that the ideal doping cation must have a low electronegativity and a small ionic radius (r) associated with high effective nuclear charge (Z*). Indeed , such a cation having high value of Z*/r 2 will polarize the electron cloud of oxygen 2p6 valence band more strongly, thereby screening its charge so as to weaken it as a scattering center. Moreover, a low electrronegativity for the dopant cation accounts for a weak interaction between the conduction band electrons and the dopant cation. Zhang established an empirical equation relating the Lewis acid strength of the cation, L its electronegtativity, and the Z*/r 2 value as L = Z*/r 2 7.7X + 8.0 (1) Under such a circumstance, a high L value of the doping cation necessarily means a reduced scattering effect (and thereby a reduced scattering cross section) of the doping cation with regard to the conduction band electrons. Therefore, when the factor dominating the mobility is the scattering of electrons from the ionized donor centers, higher (lower) mobilities will occur for semiconductors doped with donor elements having higher (lower) L values (2,3,4). Following this guideline, it appeared that the use of Ge4+ as a doping element in ITO (partially or totally substituted to Sn4+) could induce an enhancement in the mobility since L Ge 4+ = 3.06 L Sn 4+ = 1.62 (2) Consequently , we can obtain the following expression after simple transformation Q Ge 4+ /Q Sn 4+ = 0.55 (3) It is interesting to note that for similarly heavily doped ITO and IGO (such as f and k) the value obtained above is close to the ratio calculated based on the Lewis acid strengths . Using relation (2) we get L Sn 4+ /L Ge 4+ = 0.53 (4) This result confirms the expected close relation between the scattering cross section of the dopant ion and its Lewis acid strength. It appears that when the factor dominating the mobility is the scattering of electrons from the ionized donor centers, L roughly varies inversely as Q. We note here that the concepts we have put forward also apply for other degenerate oxides having a predominant ionic-bond character as we have recently investigated. C. Marcel, J. Salardenne, S. Y. Huuang, G. Campet, and J. Portier, Active and Passive Elec.Comp.1997, Vol. 19, 217-223 S. J. Wen, G. Campet, J. Portier and J. Goodenough Mat.Science and Eng. , 1992, B. 14, 115. G. Campet, S. D. Han, S. J.Wen, J. P. Manaud, J. Portier, Y. Xu and J. Salardenne, Mat. Sci. and Eng. , B (accepted for publication 1995). S. J. Wen, doctoral thesis, University of Bordeaux I, 1992. Y. Zhang. Inorg. Chem., 1982, 21, 3886, 3889 .
Yonghe Zhang ionocovalent theory applications (10) Zhang Lewis-Acid Strength is Derived from Ionocovalent Function Yonghe Zhang Inorg. Chem ., 21, 3889. Based on his ionocovalent theory Zhang proposed A Scale for the Strengths of Lewis Acids : The Lewis acid strengths could be composed of some electrostatic and some covalent properties. The electrostatic force between a positive charge and a negative charge is approximately proportional to Z/ r k 2 , where Z is the charge number of the atomic core (i.e. the number of valence electrons) and r k is the ionic radius, that operate in such a way that the stability of the complex rises with the increase in charge of the metal ion and fall with an increase in its radius. Apart from electrostatic force there appears to be covalent force. Since the -bond is formed by sharing of an electron pair between the metal ion and the ligand, its strength is bound to increase with the tendency of the cation to take electrons, i.e., with increasing electronegativity of the metal ion involved. The electronegativity values we have adopted here are the ones in valence states that we proposed previously . The othe electronegativity values as shown by f values of ref 11 in Table I, could not obtain very good results. The quantity Z/ r k 2 was calculated, with use of ionic radii mainly from Shannon and Dean . Thus the ideal results, as shown in Figure 1, are obtained by plotting Z/ r k 2 against X z . The equation for classification is derived as Z/ r k 2 7.7X z + 8.0 =0 (3) and we define the function Z as the scale for strengths of Lewis acids by Z = Z/ r k 2 7.7X z + 8.0 =0 (4) The values of the scales for the strengths of 126 metal ion of Lewis acids are calculated from equation 4 and listed in Table 1. The Z value gives a quantitative order of relative Pearson hardness or softness for the various Lewis acids and agrees fairly well with the previous classifications . Zhang, Y. (1982). Inorg. Chem., 21, 3889. Zhang, Y. (1982). Inorg. Chem., 21, 3889. Shannon ， R.D. (1976). Acta Crystallogr., Sect. A32,751. Dean, J.A. (1973). Langes Handbook of Chemistry, 11 th ed., McGraw-Hill , New York , pp.3-118. Pearson, R. G. (1963). J. Am. Chem. Soc., 85, 3533; (1968). J. Chem. Educ., 45, 581. Pearson, R. G. (1973). In: Dowden (Ed.), Hard and Soft Acids and Bases. Hutchinson and Ross Inc.,Stroudsburg. Klopman, G. (1968). J. Am. Chem. Soc., 90, 223. Yingst, A. and McDaniel, D. H. (1967). Inorg. Chem., 6, 1076. Ahrland, S. (1968). Chem. Phys. Lett., 2, 303; (1966). Struct. Bond., 1, 207
标签: Strength
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