Real-time approximation of molecular interaction interfaces based on hierarchical space decomposition

The interaction interface between two molecules can be represented as a bisector surface equidistant from the two sets of spheres of varying radii representing atoms. We recursively divide a box containing both sphere-sets into uniform pairs of sub-boxes. The distance from each new box to each sphere-set is conservatively approximated by an interval, and the number of sphere-box computations is greatly reduced by pre-partitioning each sphere-set using a kd-tree. The subdivision terminates at a specified resolution, creating a box partition (BP) tree. A piecewise linear approximation of the bisector surface is then obtained by traversing the leaves of the BP tree and connecting points equidistant from the sphere-sets. In 124 experiments with up to 16,728 spheres, a bisector surface with a resolution of 1/2⁴ of the original bounding box was obtained in 28.8 ms on average.     

碱性电池密封胶塞的防爆

碱性电池密封胶塞的防爆问题实际上是高分子材料的断裂问题。文章引述了分子理论和Griffith理论,从这两个理论角度阐述了胶塞的防爆压力受生产、贮存、温度过程中一系列复杂的物理、化学变化的影响,提出了确保胶塞质量等采取的措施。     

利用分子理论估算二甲醚的热物理特性参数

为了对二甲醚喷雾及燃烧过程进行数值模拟，根据分子理论对二甲醚的饱和蒸气压、液体黏度、汽化潜热、表面张力、热导率和扩散系数等热物理参数与温度的关系式进行估算。由于二甲醚为非极性分子，估算获得相当好的准确性。估算所得的二甲醚热物理特性参数完全可满足喷雾和燃烧过程数值模拟的要求。分子理论还为其他未知燃料热物理特性的获取提供了一种新的途径。     

分子蒸馏及其在多不饱和脂肪酸中的应用

阐述了分子蒸馏的基本原理及其主要特点。介绍了分子蒸馏在不饱和脂肪酸方面的应用研究成果。     

新型聚羧酸系高效减水剂的合成实验研究

通过正交实验,得出聚合度不同的聚氧乙烯基烯丙酯大单体的最佳合成条件：采用丙烯酸与聚乙二醇的摩尔比为1．2：1．0,阻聚剂为聚乙二醇质量的0．40％,对甲苯磺酸用量为丙烯酸用量的10％,反应温度为95℃,在充分搅拌的情况下进行烯丙酯大单体的合成。通过对自由基共聚合的聚合工艺实验,找出了最佳共聚合工艺：n（MAS）：n（AA）：n（PA）=1．5：5．0：1．25,在85℃不断搅拌下反应时间4h得到聚羧酸系减水剂。将自制的聚羧酸减水剂按相关行业标准进行性能检测并与其它商品减水剂进行性能比较,结果表明,该减水剂除具有很高的分散性外,还具有控制坍落度损失小及抗压强度比高等优点。     

水对微波场损耗机理的研究

水分子是一种强极性分子，在外加交变电场作用下，将产生很强的取向极化，与此同时还将产生位移极化，因此介质内部及表面上便出现宏观的电荷和电流分布。极化电流的产生必定会带来相应的热损耗，从该角度出发，研究水对微波场的损耗。以自由水为研究对象，建立了相关的理论模型，并加以公式推导。     

论水溶性润滑添加剂的研究方法

在已知的油溶性润滑添加剂分子中，引入水溶性基团，可以改性成水溶性润滑添加剂，在一个分子中同时包含水溶性、吸附性、疏水性、反应性基团，是合成兼有油性剂和极压剂功能的高效水溶性润滑添加剂的方法。     

1H-NMRD and17O-NMR assessment of water exchange and rotational dynamics of two potential MRI agents: MP-1177 (an extracellular agent) and MP-2269 (a blood pool agent)

The parameters that govern water proton magnetic relaxation (e.g. water exchange rates, and rotational and electronic correlation times) of representatives of two classes of Gd(III) complexes have been estimated, using two different approaches and the results compared with those derived for known analogs. The complexes studied are: (i) the non-ionic GdDTPA-bis(methoxyethyl-amide) [Gd(DTPA-BMEA)], a typical small-molecule extracellular MR agent, and (ii) the ionic Gd(III) complex of 4-pentylbicyclo[2.2.2]octane-1-carboxyl-di-l-aspartyl-lysine-derived-DTPA [GdL]⁴⁻, a prototype MR blood pool agent, which binds to serum albumin in vivo through non-covalent hydrophobic interactions. An¹⁷O-NMR study of [Gd(DTPA-BMEA)] gives a water exchange rate constant ofk _ex ²⁹⁸ =(0.39±0.02)×10⁶ s⁻¹, identical to that for the bismethylamide analog [Gd(DTPA-BMA)]. Both approaches yield longer rotational correlation times for [Gd(DTPA-BMEA)], consistent with its higher molecular weight. An¹⁷O-NMR study of [GdL]⁴⁻ gives a water exchange rate constant ofk _ex ²⁹⁸ =(4.2±0.1)×10⁶ s⁻¹, identical to that for [Gd(DTPA)]²⁻. The water exchange rate on [GdL]⁴⁻ did not decrease considerably when bound to albumin, the lowest limit isk _ex,GdL-BSA=k _ex,GdL/2. Both approaches yield identical rotational correlation times for [GdL]⁴⁻, however, it was difficult to derive a consistent rotational constant for the albumin-bound [GdL]⁴⁻ using the different approaches (values ranged between 1.0 and 23.0 ns).     

海上作业橡皮船的研制

开发研制的ＦＹ牌海上石油勘探作业橡皮船是应用新材料、采用新工艺制造的,是生产厂有史以来规格最大、结构复杂、技术含量最高的充气胶布制品。价格仅为进口产品的３８％,为生产和使用双方创造了显著的经济效益和社会效益     

耐磨型染色臭冷杉胶合板的工艺性能研究

小分子脲醛树脂浸渍长白山臭冷杉通过染色技术改良仿制名贵木材,胶合板胶合强度的试验结果表明最佳工艺温度110℃,压力为0.5MPa,固化剂为草酸,测定其胶合强度最好,胶合强度可达到1.66MPa,沸水煮后没有出现浸剥离现象,能达到GB/T18103―2000胶合板理化性能指标;表面耐磨试验中,表面刷涂三聚氰胺树脂耐磨转数可达2100转。