Electrochemical behavior and morphology of LiB compound anode materials

Electrochemical behavior of LiB compound in LiPF6-DMC/EMC/EC was studied. And morphology of the compound was investigated by SEM. The results show that there are three discharge potential plateaus for the LiB compound, corresponding to 0.46, 0.69 and 0.8 V (vs Li+/Li) respectively, its total discharge specific capacity is up to 660 mA·h/g, only first two potential plateau can be charged, its specific capacity is 274 mA·h/g. After discharging, the morphology of the Li compound is still fibrous shape.

Growth behavior of interfacial compounds in galvanized steel joints with CuSi_3 filler under arc brazing

The galvanized steels were joined using a TIG arc brazing process with CuSi3 as the filler metal.The arcing time ranged from 1 s to 5 s with arcing current of 70 A in flowing argon.The possible reaction products at the interface were confirmed using thermodynamics,SEM,and EDS methods.The results show that a fragmention behavior in some whisker-like intermetallic compounds happens,and that there are two layers of Fe2Si and Fe5Si3 formed at the interface of the galvanized steel and copper filler.From this,the schematic cycle of the interface growth behavior of Fe/Si compounds and the fragmentation behavior of whisker-like intermetallic compounds are developed.

Behavior and Mechanisms of Deformation in Intermetallic Compound Al_(66) Mn_9Ti_(25) +La

The influence of lanthanum on the microstructure, deformed behavior, microcrack susceptibility of intermetallic compound Al 66 Mn 9Ti 25 was investigated. Adding lanthanum into intermetallic compound Al 66 Mn 9Ti 25 , the lattice parameters are not changed and the Ll 2 structure is maintained. At the same time, the dendritical grain and fine second phase are obtained, which inhibits the microcrack initiation and intergranular failure. On the other hand, the movability of dislocation is enhanced and the compressive ductility is improved. The mechanism about the role of lanthanum in intermetallic compound Al 66 Mn 9Ti 25 was discussed.

Effect of the Compound Layer of Plasma Nitriding on Thermal Fatigue Behavior of 4Cr5MoSiV1 Die Steel

With the Uddeholm self restricted method, the effect of compound layer of plasma nitriding on thermal fatigue behavior of 4Cr5MoSiV1 steel was studied by the way of adding Ar during plasma nitriding to remove the compound layer. The results show that the compound layer of plasma nitriding can delay the nucleation of heat cracks and hold back the propagation of heat cracks from surface to substrate because of its high hardness and strength. On the other land, the heat checking expands faster with the compound layer on the surface than that without it. After 3000 cycles of thermal fatigue test, both heat cracks with the compound layer are wider than the another without compound layer and the number of heat cracks of the former is more from the view of cross section.

SUBSTITUTION BEHAVIOR OF ALLOYING ELEMENTS IN INTERMETALLIC COMPOUND，TiAl

A method based on electronic structure calculation is proposed to predict the substitution behavior of elements in ordered intermetallics. The electronic structure of 20 alloying elements in TiAl is calculated using the DV-Xα cluster method The bond orders between alloying elements and surrounding atoms, Bo_Ti,Bo_Al, are used as parameters. Two lines on the Bo_Ti-Bo_Al diagram separate the elements into three groups. The elements located outside of the two lines substitute either Ti or Al atom regardless of the composition of TiAl. The substitution behavior of elements between the two lines will be affected by the Ti/Al ratio and the amount of alloying elements added Substituting sequence in multi-element alloy is discussed The prediction based on this method agrees well with the experimental results.

Comparisons of interface microstructure and mechanical behavior between Ti/Al and Ti-6Al-4V/Al bimetallic composites

The microstructure, interface thickness, element distribution and interfacial mechanical behavior of Ti-6Al-4V/Al couples prepared by an insert moulding method were investigated in depth in this paper. Moreover, Ti/Al bonding was also given as a comparison for understanding the interface bonding mechanism. It is shown that there is much thinner compact sub-layer for the interface of the Ti-6Al-4V/Al joint, whose morphology is obviously different from that of the Ti/Al joint. The Ti-6Al-4V/Al interface has been proven to contain a slight content of vanadium. Moreover, both the shear strength and the interface reaction rate of Ti-6Al-4V/Al compound materials are lower than those of the Ti/Al ones.

Magnetic transition and large reversible magnetocaloric effect in EuCu_(1.75)P_2 compound

The magnetocaloric effect（MCE） in EuCu1.75P2 compound is studied by the magnetization and heat capacity measurements.Magnetization and modified Arrott plots indicate that the compound undergoes a second-order phase transition at TC ～ 51 K.A large reversible MCE is observed around TC.The values of maximum magnetic entropy change（-△SxMma） reach 5.6 J·kg^-1·K-1 and 13.3 J·kg^-1·K-1 for the field change of 2 T and 7 T,respectively,with no obvious hysteresis loss in the vicinity of Curie temperature.The corresponding maximum adiabatic temperature changes（△Tadmax） are evaluated to be 2.1 K and 5.0 K.The magnetic transition and the origin of large MCE in EuCu1.75P2 are also discussed.

Phase transition and critical behavior of spin–orbital coupled spinel ZnV_2O_4

We present the temperature-dependent susceptibility and specific heat measurement of spinel ZnV204. The structural transition with orbital ordering and the antiferromagnetic transition with spin ordering were observed at 50 K and 37 K, respectively. By analysis of the hysteresis behavior between the specific heat curves obtained in warming and cooling processes, the structural transition was confirmed to be the first-order transition, while the antiferromagnetic transition was found to be of the second-order type. At the structural transition, the latent heat and entropy change were calculated from the excess specific heat, and the derivative of pressure with respect to temperature was obtained using the Clausius--Clapayron equation. At the magnetic transition, the width of the critical fluctuation region was obtained to be about 0.5 K by comparing with Gaussian fluctuations. In the critical region, the critical behavior was analyzed by using renormalization-group theory. The critical amplitude ratio A＋/A- = 1.46, which deviates from the 3D Heisenburg model; while the critical exponent a is -0.011, which is close to the 3D XY model. We proposed that these abnormal critical behaviors can be attributed to strong spin-orbital coupling accompanied with the antiferromagnetic transition. Moreover, in the low temperature range （2-5 K）, the Fermi energy, the density of states near the Fermi surface, and the low limit of Debye temperature were estimated to be 2.42 eV, 2.48 eV-1, and 240 K, respectively.

Influence of Bi Addition on Pure Sn Solder Joints: Interfacial Reaction, Growth Behavior and Thermal Behavior

The effects of different Bi contents on the properties of Sn solders were studied. The interfacial reaction and growth behavior of intermetallic compounds（IMCs） layer（η-Cu6 Sn5 + e-Cu3 Sn） for various soldering time and the influence of Bi addition on the thermal behavior of Sn-x Bi solder alloys were investigated. The Cu6 Sn5 IMC could be observed as long as the molten solder contacted with the Cu substrate. However, with the longer welding time such as 60 and 300 s, the Cu3 Sn IMC was formed at the interface between Cu6 Sn5 and Cu substrate. With the increase of soldering time, the thickness of total IMCs increased, meanwhile, the grain size of Cu6 Sn5 also increased. An appropriate amount of Bi element was beneficial for the growth of total IMCs,but excessive Bi（≥ 5 wt%） inhibited the growth of Cu6 Sn5 and Cu3 Sn IMC in Sn-x Bi/Cu microelectronic interconnects. Furthermore, with the Bi contents increasing（Sn-10 Bi solder in this present investigation）, some Bi particles accumulated at the interface between Cu6 Sn5 layer and the solder.

复合型灾害中公众多重应对行为特征与影响因素研究

伴随着快速的工业化、城市化、全球化,现代灾害风险正日益呈现鲜明的复合型特征。复合型灾害充斥着不确定性、紧急性与威胁性,使灾害来临时的个体应对行为实施面临着信息冲击更为混乱、决策时间更短、风险程度更高等严峻挑战。灾害情境的变化给传统灾害风险与应急管理模式带来了冲击,也对公众的多重应对能力提出了新要求。研究从2022年9月四川省部分地区居民经受突发公共卫生事件、地震自然灾害的复合型灾害场景出发,通过案例分析和结构方程模型的方法,对复合型灾害中公众多重应对行为的特征及影响因素展开探索。研究结果表明,科学的个体权衡和信息环境等因素显著影响公众的多重应对行为效能,公众在复合型灾害应对中能否做出有效的多重应对行为,是增强社会防范和应对处置灾害事故能力、提高自救、互救能力的关键。据此,应将风险情境变动特征纳入灾害宣教体系,加强灾变情境下信息整合与资源配备能力建设,同时积极制定复合型灾害应急预案并展开应急演练。研究为提高全社会抵御复合型灾害能力、筑牢防灾减灾救灾人民防线提供了有益启示。

绿豆象成虫对红豆与绿豆种子挥发物的电生理和嗅觉行为反应

【目的】明确红豆Vigna angularis与绿豆V.radiata种子挥发物对绿豆象Callosobruchus chinensis成虫嗅觉行为的影响,为筛选绿豆象行为调控剂奠定理论基础。【方法】利用固相微萃取(solid-phase microextraction,SPME)和气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)法对绿豆晋绿1号和红豆汾小豆3号种子的挥发性化合物进行提取鉴定,通过触角电位(electroantennogram,EAG)和嗅觉选择行为反应筛选对绿豆象具有引诱活性的化合物及配方,并进行田间诱捕试验。【结果】红豆和绿豆种子中的共有挥发物有18种,主要包含醛类、酮类、烯烃类、烷烃类、醇类、酯类和芳香烃类,其中含量较高的4种物质甲基庚烯酮、己醛、正壬醛和癸醛均能引起绿豆象成虫强烈的电生理反应,而正癸烷、反式石竹烯、2-甲基萘和环己基苯等引起的反应相对微弱。嗅觉选择行为反应结果表明己醛对绿豆象雌雄成虫有明显驱避作用;而甲基庚烯酮、正壬醛和癸醛对绿豆象雌雄成虫均表现出引诱作用。多组分室内行为反应试验表明,甲基庚烯酮与正壬醛以1∶2.6的比例混配时雌雄成虫选择率达到70%以上,引诱效果相对较好;而甲基庚烯酮与癸醛以1∶3.2的比例混配时雌雄成虫选择率还未达到60%,引诱效果较差。【结论】红豆与绿豆种子挥发物中甲基庚烯酮、正壬醛和癸醛对绿豆象雌雄成虫有较好的引诱活性,可能在绿豆象嗅觉识别过程中发挥重要作用,可以用于开发该害虫的行为调控剂。

金属有机框架材料在橡胶密封条除味性能中的应用

将金属有机框架材料(MOFs)作为三元乙丙橡胶(EPDM)密封条的除味剂,研究了MOFs对EPDM的硫化行为和力学性能的影响,考察了MOFs对EPDM释放出挥发性有机化合物气味的抑制效果。结果显示,MOFs的加入可促进EPDM的硫化且其力学性能基本不变;MOFs对有机胺和二硫化碳等气味分子具有较好的吸附效果,EPDM的气味等级从4.5降至2.0。

硬度对胎面胶磨损行为的影响

利用炭黑N330用量与胎面胶硬度之间的关系,研究硬度对胎面胶磨损行为的影响。结果表明:在负荷≤30 N时,随着硬度的增大,硫化胶的磨耗体积增大,在负荷≥50 N时,随着硬度的增大,硫化胶的磨耗体积减小;硫化胶的耐磨性能的转变点与摩擦能量的转变点基本一致,硫化胶在滚滑工况下的磨损量可用摩擦能量等效表示。

活化蟹壳生物质炭的制备及其在VOCs吸附中的应用

针对大气中由挥发性有机化合物不可控释放引起的环境和健康问题,开发新的吸附技术和材料是重要的解决途径之一。通过热处理廉价、无毒、可再生的蟹壳废弃物,并通过KOH活化制备了可对VOCs高效吸附的蟹壳生物质炭。以炭壳为原料制备了碳化蟹壳(CS)和蟹壳活性炭(CSK),并采用SEM、BET、FT-IR、XRD对其进行了表征,系统考察了温度对VOCs(二甲苯和正己烷)的影响,分析结果表明,制备的蟹壳生物质炭是一种具有介孔结构的多孔材料,其比表面积高达2098.15 m^(2)/g,平均孔径约为1.98 nm,孔体积为1.16 cm^(3)/g。最后,对制备的CSK-800进行了动态吸附实验,得到的二甲苯和正己烷的总吸附量分别为557.98、585.19 mg/g。吸附动力学研究结果表明,其吸附过程与准一级和Bangham模型拟合结果高度吻合,较好地诠释了蟹壳活性炭对VOCs吸附主要是以物理吸附为主的孔道扩散。

负外部性如何塑造地方政府的政策行为?——以适老化改造中加装电梯政策为例

负外部性问题是基层社会治理的关键所在。基于全国114个城市的207份加装电梯政策文件,对地方政府应对负外部性的两种政策取向及其政策转换行为进行了动态识别,分析了两种政策取向所对应的负外部性治理方式及其内生的社会治理困境。研究表明:负外部性问题内嵌于地方政府的政策行为,表现为首次政策出台和后续政策修订中有关政策取向的差异化选择和跨期变动。具体地,68.42%的样本城市以“严格”的政策取向初次设定加装电梯政策,但随着政策取向的调整,最终选择“放松”的政策取向的城市占比达71.05%;50个样本城市的政策取向发生了由“严格”向“放松”的转变,其根源并非“自上而下”的层级任务压力,而是前期政策实践为地方政府认识负外部性所带来的潜在风险规模提供了有效信息,使其对潜在冲突风险的控制力得到增强。在推动解决老旧小区加装电梯难题的社会治理实践中,应对负外部性要依靠政策规制,但不能过度依赖政策规制,提升负外部性治理能力需要在风险预判、协同推进正负外部性活动以及靶向社区双重再造等方面重点发力。

铝/钢异种金属焊接接头腐蚀行为及其影响因素综述

铝/钢异种金属焊接接头结合了两种材料优异的性能,在各行各业具有较为广泛的应用.由于铝、钢两种金属之间理化性能的巨大差异以及极小的固溶度,导致铝/钢接头容易出现脆性金属间化合物、气孔等缺陷,严重影响着接头的力学性能.然而,随着铝/钢接头越来越广的应用范围和复杂多样的应用环境,接头的耐腐蚀性能也得到了更多的关注.对近些年铝/钢异种金属焊接接头的耐腐蚀方面研究工作做了系统的汇总,旨在从接头腐蚀机理出发,提升接头的耐腐蚀性.综述了接头腐蚀形式规律,并从焊接工艺、腐蚀环境、微观组织和金属间化合物等影响因素的角度出发,详细地讨论了腐蚀行为与各因素之间的关系及影响机理.同时,指出了接头腐蚀机理,从各影响因素方面提出了改善接头耐腐蚀性能的措施,减小铝/钢接头实际服役过程中腐蚀所带来的影响.

互叶白千层及其挥发物对柑橘木虱行为选择的影响及其应用

柑橘木虱(Diaphorina citri Kuwayama)是危害柑橘嫩梢期的害虫,是柑橘黄龙病的传播媒介之一.田间调查表明互叶白千层(Melaleuca alternifolia Cheel)隔离防护带对柑橘园中的柑橘木虱起到了有效的防控作用.本研究采用气相色谱-质谱联用技术分析了广东省德庆市柑橘园种植的互叶白千层植株的挥发物组分,结合气相色谱-触角电位技术研究了柑橘木虱成虫对互叶白千层精油的触角电位反应,并利用Y型嗅觉仪测试了柑橘木虱对该植物、植物精油及其主要挥发物的行为反应.结果表明,互叶白千层生物型为4-松油醇,挥发物中含有29种化合物.柑橘木虱雌成虫触角对互叶白千层精油中的α-松油烯、 γ-松油烯和4-松油醇均有电生理反应,雄成虫触角对γ-松油烯和4-松油醇有电生理反应.行为反应测试结果表明,柑橘木虱成虫对互叶白千层枝叶具有明显驱避作用,对20μL/mL、 30μL/mL互叶白千层精油以及100μL/mL 4-松油醇亦均具有明显驱避作用,而对0.1μL/mL γ-松油烯具有明显引诱作用.本研究从行为学反应和化学成分等方面深入研究了柑橘木虱和互叶白千层间的关系,研究结果可为利用4-松油醇型互叶白千层防控柑橘木虱以及开发柑橘木虱绿色防控技术提供理论依据.

电信网络诈骗中罪名认定争议及其教义学应对

对近五年来电信网络诈骗犯罪案件判决书进行实证分析发现,该种犯罪的罪名认定在司法实践中存在关联犯罪上下扩散、罪名群内部认定混乱、帮助行为定性分歧等问题,而这主要是由电信网络诈骗犯罪法益、行为要件、既遂标准的不明确所引发。电信网络诈骗犯罪侵犯的法益具有复合性,即在财产法益之外还有网络公共秩序法益。法益复合性决定了单以诈骗罪无法完整地评价电信网络的诈骗行为,既有的司法解释忽视了电信网络诈骗在行为方式上的特殊性,采用拟制方式将其纳入诈骗罪评价范围考量,导致司法人员在罪名适用时无所适从。因此,必须通过教义学的途径明确电信网络诈骗犯罪上下游关联行为的罪名归属,从而妥善解决司法适用中的难题。

长林小蠹对黑松挥发物电生理及行为反应

为探究长林小蠹对不同生理状态黑松(Pinus thunbergii)挥发物的选择偏好性,利用动态顶空吸附法,分别收集健康和不同受害程度的黑松树干和树根的挥发物,通过气相色谱-质谱联用仪(Gas chromatography-mass spectrometry,GC-MS)对收集的挥发物进行鉴定与分析,采用触角电位仪(Electroantennagraphy,EAG)和Y形嗅觉仪,分析鉴定到的黑松中主要挥发物及其他人鉴定到的黑松中主要挥发物对长林小蠹的电生理和行为影响。结果表明,健康和不同受害程度的黑松树干、树根的挥发物在组成和含量上部分差异显著(P<0.05)。树干中主要化合物(1R)-(+)-α-蒎烯的相对含量由健康木转向萎蔫木阶段呈下降趋势,在萎蔫木到枯死木阶段相对含量上升。而树根由健康木阶段转向濒死木阶段时(1R)-(+)-α-蒎烯的相对含量逐渐减少,在枯死木阶段其相对含量有所上升。EAG测试结果显示,在测定的10种挥发物中,有9种引发的雌成虫和雄成虫EAG反应值之间有显著差异。其中,雌虫对0.1 mg/mL的(1S)-(-)-α-蒎烯的反应值最高,雄虫对0.01 mg/mL的罗勒烯反应值最高。Y形嗅觉仪行为反应结果显示,不同质量浓度的挥发物对长林小蠹雌雄虫的作用不同。0.01~100 mg/mL的α-蒎烯、100 mg/mL的α-松油烯、10 mg/mL和100 mg/mL的(1S)-(-)-α-蒎烯、(1R)-(+)-α-蒎烯对长林小蠹雌雄成虫都有较强的吸引作用,10 mg/mL的(-)-β-蒎烯对长林小蠹雌雄成虫都有较强的驱避作用。由此,0.01~100 mg/mL的α-蒎烯;100 mg/mL的α-松油烯、10 mg/mL和100 mg/mL的(1S)-(-)-α-蒎烯、(1R)-(+)-α-蒎烯可以作为长林小蠹雌雄成虫引诱剂成分,10 mg/mL的(-)-β-蒎烯可作为长林小蠹成虫驱避剂成分。

复配成核剂改性尼龙6的结晶行为和力学性能

本文使用芥酸酰胺与褐煤蜡酸钙成核剂(TMN-102)复配制备复配型成核剂(TMN-102E)以期达到促进TMN-102在尼龙6(PA6)中的分散并研究了复合体系的结晶行为和力学性能。结果表明,TMN-102与芥酸酰胺的复配未改变TMN-102的分子结构。TMN-102可以显著加快PA6的等温和非等温结晶速率,在同一降温速率下的结晶温度和结晶度随着TMN-102的添加而提高。同时,随着TMN-102的添加,样品的非等温结晶活化能降低。这说明TMN-102可以作为PA6的有效成核剂提高其结晶性能。另外,与TMN-102E在PA6基体中的分散性大幅改善,这一改善也使其拥有比TMN-102更优异的成核效果。最后,TMN-102的添加可以通过提高PA6晶体完善程度的方式提高其缺口冲击强度和拉伸强度,且随着TMN-102E在PA6基体中均匀分散这一提高更加明显。