A Novel Test for the Appraisal of Solid/Solid Interfacial Interactions

The Johnson, Kendall and Roberts (JKR) technique has been used with considerable success for assessing solid/solid interfacial interactions over the past 25 years or so. Nevertheless, the contact zone between the two spherical solids is often small and the energy of adhesion scales with the cube of the contact radius (at low load), thus potentially magnifying errors in adhesion assessment. The theoretical aspects of a novel technique are presented here, in which a hollow, slightly inflated, spherical membrane replaces a full sphere, and is placed in contact with a flat rigid solid. A judicious choice of experimental conditions should lead to increased contact radius and the energy of adhesion scales with its square (at low load), thus reducing possible errors. An added advantage is that the effective elasticity of the sphere depends on internal gas pressure. Thus surface and bulk effects are decoupled.     

Adhesion Between Rubbers and Grafted Solids

The adhesion energy, G (at low separation velocities), between a rubber and a solid surface, is expected to increase when flexible chains, chemically identical to the rubber, are attached to the surface. This can be set up with or without chemical binding of the chains to the rubber (“bound” chains or “free” chains).     

清茗入佳壶,韵致自道来——漫谈“清韵壶”的意境

以紫砂清韵壶为例,从题材选取、造型装饰及文化内涵等方面展开论述,彰显紫砂清韵壶的意境之美。     

LC-MS/MS检测新型“香料”毒品1例

目的:对缴获的疑似香料毒品进行检验。方法:采用LC-MS/MS方法对缴获的样品进行定性和定量分析。结果:检出合成大麻素JWH-018成分,含量为0.67%。结论:该成分是一种大麻素受体激动剂,属于策划药,该检材属于新型滥用药物。     

“双碳”形势下煤炭工业未来发展的思考

针对“双碳”目标,提出煤炭工业面临的变化以及未来随着新技术的出现,煤炭工业可能的发展趋势,并提出相关建议。     

The Complex Roles of Adenosine Triphosphate in Bioenergetics

ATP is generally defined as the “energy currency” of the cell. Its phosphoanhydride P−O bonds are often considered to be “high energy” linkages that release free energy when broken, and its hydrolysis is described as “strongly exergonic”. However, breaking bonds cannot release energy and ATP hydrolysis in motor and active transport proteins is not “strongly exergonic”. So, the relevance of ATP resides elsewhere. As important as the nucleotide are the proteins that undergo functionally relevant conformational changes upon both ATP binding and release of ADP and inorganic phosphate. ATP phosphorylates proteins for signaling, active transport, and substrates in condensation reactions. The ensuing dephosphorylation has different consequences in each case. In signaling and active transport the phosphate group is hydrolyzed whereas in condensation reactions the phosphoryl fragment acts as a dehydrating agent. As it will be discussed in this article, ATP does much more than simply contribute free energy to biological processes.     

计算机研究生选修课套餐制度研究

计算机专业多样的发展方向以及庞大的知识体系结构,让选课成为了一件棘手的事情。文章从一个全新的角度提出了适用计算机研究生的选修课“套餐”选课制度,通过分析不同研究方向的侧重点,为大部分高校目前设立的多个研究方向确定了选修课“套餐”。套餐选课制度能减少计算机研究生选课时的盲目性,有效地提高学生的学习效果,促进计算机专业人才的培养。     

Molecular Dynamics of Synthetic Flagelliform Silk Fiber Assembly

In order to better understand the relationship between flagelliform (Flag) spider silk molecular structural organization and the mechanisms of fiber assembly, the Nephilengys cruentata Flag spidroin analogue rNcFlag2222 is designed and produced. The recombinant proteins are composed by the elastic repetitive glycine-rich motifs (GPGGX/GGX) and the spacer region, rich in hydrophilic charged amino acids, present at the native silk spidroin. Using different approaches for nanomolecular protein analysis, the structural data of rNcFlag2222 recombinant proteins are compared in their fibrillar and fully solvated states. Based on the results, it is possible to identify the molecular structural dynamics of NcFlag2222 prior to and after fiber formation. Overall rNcFlag2222 shows a mixture of semiflexible and rigid conformations, characterized mostly by the presence of polyproline type II helix (PPII), β-turn, and β-sheet. These results agree with previous studies and bring insights about the molecular mechanisms that might drive Flag silk fibers assembly and elastomeric behavior.     

随机交叉-自学策略改进的教与学优化算法

针对非原点最优的复杂优化问题(最优解不在坐标原点),提出了一种基于随机交叉-自学策略的教与学优化算法(teaching and learning optimization algorithm based on random crossover-self-study strategy, CSTLBO)。对标准教与学优化算法的“教阶段”和“学阶段”的空间扰动进行了几何解释,改进了原有的“教阶段”和“学阶段”,并引入随机交叉策略和“自学”策略来提高算法的全局寻优能力。通过使用20个Benchmark函数进行仿真,并与6种改进的教与学优化算法进行结果比较及Wilcoxon秩和检验分析,结果表明CSTLBO算法能有效避免陷入局部最优,具有良好的全局搜索能力,求解精度高,稳定性好。     

发挥新型举国体制优势解决装备“卡脖子”问题的研究

对新型举国体制与传统举国体制进行了区分,列举了新型举国体制的优势,分析了新型举国体制与市场经济的关系,探究了新型举国体制解决装备“卡脖子”问题的方式,并就解决机床工具行业“卡脖子”问题给出了相应的政策建议。