The impact of cellulose structure on binding interactions with hemicellulose and pectin

Four cellulose substrates including highly crystalline cellulose nanowhiskers (CNWs) from Gluconacetobacter xylinus (cellulose Iα) or cotton (cellulose Iβ) and amorphous cellulose derived from CNWs (phosphoric acid swollen cellulose nanowhiskers, PASCNWs) were used to explore the interaction between cellulose and well-defined xyloglucan, xylan, arabinogalactan and pectin. The binding behavior was characterized by adsorption isotherm and Langmuir models. The maximum adsorption and the binding constant of xyloglucan, xylan and pectin to any CNWs were always higher than to PASCNWs derived from the same source. The binding affinity of xyloglucan, xylan and pectin to G. xylinus cellulose was generally higher than to cotton cellulose, showing that binding interactions depended on the biological origin of cellulose and associated differences in its structure. The surface area, porosity, crystal plane and degree of order of cellulose substrate may all impact the interactions.     

Direct Henry reactions with modified calcium oxide as solid catalyst

Commercial CaO was modified simply with benzyl bromide. The modified CaO had good water resistance, and characterization by FTIR and TG revealed the modifier was chemically bonded to the CaO surface. Commercial CaO and CaO modified with benzyl bromide were investigated as catalysts for the Henry reaction between benzaldehyde and nitromethane. It was found that the catalytic activity of the modified CaO was greatly improved, with high conversion of benzaldehyde to the (E)-phenyl nitroolefin and 1-phenyl-2-nitroethanol, and with different selectivity from commercial CaO. The effect of modification and reaction conditions on yield, selectivity, and mechanism were studied thoroughly.     

Experimental study of enhanced emission of the laser-ablated plume in backing gas

The effects of background gases on the optical emission of the excimer-laser-ablated plume from a brass target have been studied experimentally. It is found that the plume emission can be enhanced significantly in a proper gas ambient. In hydrogen, the highest peak intensity is detected, and in argon, there is a distinctive difference in the pressure-dependent emission between in He and in the other three gases, Ar, N₂ and H₂. Moreover, the monitored line peak intensity remains unchanged in Ar and N₂ and increases in H₂ within a distance above the target surface; but in He, the observed peak intensity decreases with distance like in vacuum. Furthermore, the emissions of several more atomic lines of Cu and Zn atoms from the plume are also found to be enhanced in the same manner in gas ambient. Some physical processes involved in the plume expansion and the possible mechanisms for the enhanced emission of the plume in backing gas are discussed.     

3-甲酰腙一利福霉素SV及其异构体的研究

用发酵和化学法合成的两个3-甲酰腙-利福霉素SV样品(1^#,2^#)具有不同的物理化学性质,本文用多种NMR技术,如¹H,¹³C,DEPT,¹H-¹H COSY,反相摸式的¹H-¹³C COSY及远程¹H-¹³C COSY,并结合红外及紫外一可见光谱测试结果进行综合分析,确定样1^#及样2^#分别为酰胺式主产品及亚胺醇式导构体。根据实验结果对样1^#的异构化反应进行了初步的探讨.     

Size dependence of a magnetopolaron in cylindrical quantum wires at arbitrary magnetic fields

With the use of variational method to solve the effective mass equation, we have studied the cyclotron resonance of a magnetopolaron in cylindrical quantum wires at arbitrary magnetic fields. The interaction of the electron with surface-optical (SO) phonons is used. Having calculated the ground state energy and the excited state energy of the magnetopolaron, we obtain the hybrid frequency of the magnetopolaron in quantum wires.     

毛细管区带电泳分析阿片受体和抗独特型抗羟甲芬太尼抗体

应用毛细管区带电泳（ＣＺＥ）分析测定阿片受体、抗独特型抗羟甲芬太尼抗体等生物大分子样品。熔融石英毛细管柱为６０ｃｍ×１００μｍｉ．ｄ．（从进样到检测器长度为５０ｃｍ）,以硼砂－氢氧化钾为缓冲液。结果表明缓冲液的ｐＨ影响ＣＺＥ对阿片受体的分析,当ｐＨ为９．０时分析效果最理想,重现性良好,测得的两个主峰与同批样品进行ＳＤＳ－ＰＡＧＥ分析得到的两个条带相符。用ＣＺＥ分析抗独特型抗羟甲芬太尼抗体（ＩｇＧ）,表明用ＰｒＯｔｅｉｎＡ－Ｓｅｐｈａｒｏｓｅ亲和色谱分离得到部分纯化的ＩｇＧ,迁移时间不同于对照豚鼠的ＩｇＧ。     

工作机械相对振动的研究

本文对工作机械的相对振动进行了理论和实验研究。分析了相对振动的激励和合成原理,提出了工件和工具同相振动和异相振动、同相域以及相对振动放大因子等概念。在此基础上指出了减小相对振动的途径,以作为设计和改造工作机械的参考。     

Loading aircraft for military operations

In this paper, we describe an aircraft loading problem submitted by the French military agency (DGA) as part of a more general military airlift planning problem. It can be viewed as a kind of bi-dimensional bin-packing problem, with heterogeneous bins and several additional constraints. We introduce two-phase methods for solving this NP-hard problem. The first phase consists in building good initial solutions, thanks to two fast algorithms: a list-based heuristic and a loading pattern generation method. Both algorithms call a constraint-based subroutine, able to determine quickly if the items already loaded can be reshuffled to accommodate a new object. The second phase improves these preliminary solutions using local search techniques. Results obtained on real data sets are presented.