碳铵化肥发青问题解决小结

探讨了该厂化肥生产中碳铵发青的原因,通过硫化氢含量的测定,分析了系统内外影响因素,提出了解决措施,达到了不停车稳定产品质量的目的。     

Chemistry of hydrogen sulphide under coal liquefaction conditions: 1. Modelling hydrogen transfer catalysis

The work reported here represents initial attempts to develop a complete kinetic and mechanistic understanding of the reaction chemistry of H₂S under coal liquefaction conditions, using both model systems and coal. Hydrogen sulphide was found to promote/catalyse the transfer of hydrogen from tetralin to 2-hydroxyquinoline (2-HOQ). The presence of H₂S can increase the rate of hydrogen transfer from tetralin to 2-HOQ by a factor of 10 compared with the same reaction run in the absence of H₂S. The energy of activation for hydrogen transfer was found to decrease by ≈5 kcal mol⁻¹ in the presence of H₂S. The presence of H₂S was also found to promote loss of oxygen from 2-HOQ to form small amounts of quinoline. No evidence of CC or CN bond cleavage in 2-HOQ was noted under any of the reaction conditions studied. These results suggest that the presence of H₂S reduces the temperatures necessary to promote effective hydrogen transfer from tetralin by 50–75 °C. Moreover, they imply that similar effects occur in H₂S-promoted coal liquefaction.     

基于S3C6410的远程无线环境监测系统设计

从实际应用出发并结合近年来环境监测技术的发展趋势,设计了一套以S3C6410为主要硬件平台、以嵌入式Linux为主要软件平台的远程环境监测系统。该系统采用B/S架构,具有低成本、低功耗、高稳定的特点。用户通过Internet上的任何终端(如电脑、手机等)来访问该系统,可非常方便地对监测区域进行实时的监测。该系统支持多个用户同时登陆,兼容多种浏览器,具有较高的安全性,在环保行业、制造行业、交通行业的环境监测方面具有一定的推广应用价值。     

Asymmetric Sharpless epoxidation of 13S‐hydroxy‐ 9Z, 11E‐octadecadienoic acid (13S‐HODE)

The asymmetric Sharpless epoxidation of methyl 13S‐hydroxy‐9Z, 11E‐octadeca‐dienoate (13S‐HODE, 1 ) with tert‐butyl hydroperoxide (TBHP) catalysed by titanium tetraisopropoxide {Ti(ⁱOPr)₄} in the presence of L(+)‐diisopropyl tartrate (L‐DIPT) gave methyl 13S‐hydroxy‐11S, 12S‐epoxy‐9Z‐octadecenoate 2 (erythro isomer) in 84% diastereomeric excess (de). The epoxidation of 1 with TBHP catalysed by Ti(ⁱOPr)₄ in the presence of D(‐)‐DIPT yielded methyl 13S‐hydroxy‐11RR12R‐epoxy‐9Z‐octadecenoate (threo isomer) 3 in 76% de.     

Characterization of microporous-mesoporous MCM-41 silicates prepared in the presence of octyltrimethylammonium bromide

MCM-41 silicates prepared in the presence of octyltrimethylammonium bromide either by a conventional method or by post-synthesis hydrothermal treatment were characterized by nitrogen adsorption in a wide range of relative pressure from 10^-6 to 1. Hydrothermally restructured samples were found to have lower BET surface areas, lower external surface areas and thicker silica walls than the non-treated sample. More importantly, in addition to their characteristic mesopores (ca. 3 nm), they were shown to have considerable amounts of micropores. The relative amount of micropores and mesopores was shown to be dependent on the treatment conditions. Thus, it is demonstrated that the postsynthesis hydrothermal restructuring is a convenient synthesis route to MCM-41 silicates with bimodal pore size distribution involving controllable amounts of microporosity. This revised version was published online in July 2006 with corrections to the Cover Date.     

Viscous flow past a porous sphere with an impermeable core : effect of stress jump condition

An arbitrary flow of a viscous, incompressible fluid past a porous sphere of radius `a' with an impermeable core of radius `b', using Brinkman's equation in the porous region is discussed. At the interface of the clear fluid and porous region, stress jump boundary condition for the tangential stresses along with the continuity of normal stresses and the velocity components are used. On the surface of the impermeable core no slip condition is used. The corresponding Faxen's laws are derived to compute the drag and torque acting on the surface r=a. It is found that the drag and torque not only change with the change of the permeability, but also a significant effect of the stress jump co-efficient is observed. The variation of drag and torque with permeability for different thickness (a-b) of the porous region as well as for different values of stress jump coefficient is discussed when the basic flow is due to uniform flow, two dimensional irrotational flow, doublet in a uniform flow, stokeslet, rotlet. In case of uniform flow the flow field has been plotted. In all the cases, a significant effect of the stress jump coefficient has been realized.     

Android平台i-Jetty服务器在智能家居中的应用研究

针对智能家居系统架构复杂、开发难度较大等问题,提出了一种基于Android平台嵌入式Web服务器i-Jetty的智能家居系统方案。在ARM硬件平台及Android软件平台上,采用i-Jetty服务器实现了家居环境信息网络远程监控功能。系统以Mini6410开发板为中央控制器、服务器和室内监控平台,采用蓝牙与被控设备进行通信,通过Linux层驱动加载、Android本地服务和Web服务的联合编程,实现对传感器数据的获取、家电控制和信息发布。实验结果证明了方案的可行性和实用性。     

Klebsieila sp．601细菌漆酶的鉴定及性质

从森林树木根部土壤中分离得到一株具有2，6-二甲氧基酚（DMP）和2，2＇-连氮基-双（3-乙基苯丙噻唑啉-6磺酸（ABTS）氧化活性的细菌。Cu^2＋、Ca^2＋、Mn^2＋、Fe^2＋和Mg^2＋可诱导细菌表达活性的胞质可溶性单体酶蛋白。该酶进行DMP或ABTS氧化时需要铜离子的协助，在pH5．0～7．5范围内氧化DMP，在pH4．0～4．5范围内氧化ABTS，但不能氧化酪氨酸。SDS-PAGE估测酶蛋白分子量大约为55kD。经60℃处理4h或pH10条件下透析20h仍能保持酶活性。16S rDNA序列分析结合常规细菌形态学分析，表明该细菌属于克雷伯氏菌（Klebsiella）属，并命名为Klebsiella sp．60l。这是首例报道Klebsiella细菌菌株具有漆酶活性。     

Structure–Function Relations in Supported Ni–W Sulfide Hydrogenation Catalysts

Ni–W catalysts were prepared by impregnation of commercial -alumina and silica supports. The sulfidation, performed directly after drying at 100°C, yielded fully sulfided Ni–W species on both supports (SEM-EDAX, XPS, XRD). At optimal metals loading (50 wt% NiO + WO₃, Ni/W = 2), the sulfided catalysts had similar texture (N₂ adsorption) and displayed similar activity in dibenzothiophene hydrodesulfurization (DBT HDS), while the activity of the Ni–W/SiO₂ catalyst in toluene hydrogenation (HYD) was six times higher than that of Ni–W/Al₂O₃. This is due to the more than two times higher WS₂ slabs stacking number in Ni–W/SiO₂ compared with Ni–W/Al₂O₃ (XRD, HR-TEM), yielding stronger adsorption of toluene (TPD).     

纺织企业的原料库存控制模型研究

合理控制库存量,降低原料库存成本对纺织企业提高市场竞争力具有重大的意义。通过建立原料库存的不定量不定期控制模型,并采用遗传算法求解,给出了满足平均库存成本最小的(s,S)控制策略,并通过实例验证算法的有效性。