电化学预处理碳纤维电极用于毛细管电泳安培检测局部麻醉药

本文研究了电化学预处理碳纤维的各种条件,如处理电压、处理时间、处理后稳定时间、溶液条件等对局部麻醉药普鲁卡因、利多卡因电化学行为的影响.找出的电化学预处理最佳条件是在2.0V进行1.5min阳极化处理并在缓冲液中保持10min.普鲁卡因在pH=4~5之间,利多卡因在pH=6~7之间有较低的峰电位.运用最佳条件,普鲁卡因和利多卡因在毛细管电泳上5min内可获得很好的分离和检测.

(η~5-C_5H_5)_2Yb(THF)_2的新合成方法及其晶体结构

双(环戊二烯基)镱(Ⅱ)四氢呋喃配合物(η~5-C_5H_5)_2Yb(THF)_2通过环辛二烯基钾(KC_8H_(11))还原(C_5H_5)_2YbCl·THF而得到,经元素分析、红外光谱表征,并测定了其晶体结构。配合物属单斜晶系,C2/c空间群,晶体学参数a=1.3564(4),b=0.9569(3),c=1.4747(6)nm;β=109.90(3)°;V=1.79975(118)nm~3;D_c=1.65·cm~(-3);μ_C=54.7cm~(-1)(Mo);F(000)=880,Z=4。最后一致性因子R=0.079,R_w=0.081。Yb~(2+)的配位数为8。

彩色照相冲洗套药生产过程的在线分析方法研究

本文介绍彩色显影套药生产过程中几种成分在线分析方法,包括样品连续采集与稀释、干扰、选择性、测量范围、输出特性、响应时间及稳定性等,为专用的变换器设计和研制提供了依据。

Haematopoietic lineage cell-specific protein 1 (HS1) promotes actin-related protein (Arp) 2/3 complex-mediated actin polymerization

HS1 (haematopoietic lineage cell-specific gene protein 1), a prominent substrate of intracellular protein tyrosine kinases in haematopoietic cells, is implicated in the immune response to extracellular stimuli and in cell differentiation induced by cytokines. Although HS1 contains a 37-amino acid tandem repeat motif and a C-terminal Src homology 3 domain and is closely related to the cortical-actin-associated protein cortactin, it lacks the fourth repeat that has been shown to be essential for cortactin binding to filamentous actin (F-actin). In this study, we examined the possible role of HS1 in the regulation of the actin cytoskeleton. Immunofluorescent staining demonstrated that HS1 co-localizes in the cytoplasm of cells with actin-related protein (Arp) 2/3 complex, the primary component of the cellular machinery responsible for de novo actin assembly. Furthermore, recombinant HS1 binds directly to Arp2/3 complex with an equilibrium dissociation constant (K-d) of 880 nM. Although HS1 is a modest F-actin-binding protein with a Kd of 400 nM, it increases the rate of the actin assembly mediated by Arp2/3 complex, and promotes the formation of branched actin filaments induced by Arp2/3 complex and a constitutively activated peptide of N-WASP (neural Wiskott-Aldrich syndrome protein). Our data suggest that HS1, like cortactin, plays an important role in the modulation of actin assembly.

Sedimentation rates and provenance analysis in the Southwestern Okinawa Trough since the mid-Holocene

As a high-sedimentation rate depocenter along the path of the Kuroshio Current, the southwesternmost part of the Okinawa Trough is a key area to understand the Kuroshio history and sediments transportation. A 34.17-m-long sediment core was obtained by the advanced piston corer of Marco Polo/IMAGES XII MARION DUFRESNE during the May 2005 from the Southern Okinawa Trough at site MD05-2908. The recovered sediments were analyzed by AMS C-14 dating, coarse size fraction (> 63 mu m) extraction and moisture content determination in order to study its sedimentation flux and provenance. The depth-age relationship of core MD05-2908 was well constrained by 17 C-14 dating points. The sediments span across the mid-Holocene (6.8 ka B.P.) and have remarkablely high sedimentation rates between 1.8 and 21-2 m/ka, which is well consistent with the modern observations from sediment traps. We identified five 70-200 a periods of abnormally rapid sedimentation events at 6790-6600 a B.P., 5690-5600 a B.P., 4820-4720 a B.P., 1090-880 a B.P., and 260-190 a B.P., during which the highest sedimentation rate is up to 21-2 m/ka. In general, the lithology of the sediments were dominated by silt and clay, associated with less than 5% coarse size fraction (a parts per thousand << 63 mu m). As the most significant sediment source, the Lanyang River in northeastern Taiwan annually deliver about 10Mt materials to the coastal and offshore region of northeast Taiwan, a portion of which could be carried northward by currents toward the study area. Therefore, we concluded that the 5 abnormally rapid sedimentation events may be related to intensified rainfall in Taiwan and thus increased materials to our study area at that time. However, a few extreme-rapid sedimentation events cannot be explained by normal river runoff alone. The large earthquakes or typhoons induced hyperpycnal discharge of fluvial sediment to the ocean may also act as a potential source supply to the Okinawa Trough.

红树林植物木榄和一株海藻内生真菌的化学成分研究

本论文对民间药用红树植物木榄（Bruguiera gymnorrhiza）中的次生代谢产物进行了研究，同时还对分离自似瘤凹顶藻（Laurencia similis Namet Saito）的内生真菌EN21（Exophiala oligosperma）进行了化学成分研究。对分离得到的部分化合物进行了初步的DPPH自由基清除活性和抗菌活性筛选。 采用常规的硅胶柱层析、反相硅胶柱层析、制备薄层层析、凝胶Sephadex LH-20 柱层析、半制备型高效液相色谱（HPLC）以及重结晶等手段，从木榄（Bruguiera gymnorrhiza）中分离得到23个化合物；从EN21（Exophiala oligosperma）中分离得到23个化合物。利用一维、二维核磁、质谱、元素分析等各种现代波谱技术及化学反应方法，确定了木榄中20个化合物的结构，包括黄酮单体化合物5个，三萜类化合物11个，甾体化合物2个，长链烷烃2个，其中4个化合物为首次从木榄中报道的黄酮；确定了EN-21中20个化合物的结构，其中脑苷脂1个，甾体化合物7个，芳环化合物3个，三萜类化合物2个，包括1个新天然产物。本文系首次报道Exophiala oligosperma 的化学成分。 对从木榄中分离得到的部分化合物进行了DPPH自由基清除活性筛选， 发现黄酮类化合物BRG-1、BRG-2、BRG-3 、BRG-4显示了较强的DPPH自由基清除活性，而三萜类化合物则未表现出DPPH自由基清除活性。抗菌筛选实验中所有测试样品未显示出活性。 研究结果充实了红树林植物和海藻内生真菌代谢产物的内容，为其有效利用提供了一定的科学依据。

Corrosion behaviour of hot dip zinc and zinc-aluminium coatings on steel in seawater

A comparative investigation of hot dip Zn-25Al alloy, Zn-55Al-Si and Zn coatings on steel was performed with attention to their corrosion performance in seawater. The results of 2-year exposure testing of these at Zhoushan test site are reported here. In tidal and immersion environments, Zn-25Al alloy coating is several times more durable than zinc coating of double thickness. At long exposure times, corrosion rate for the Zn-25Al alloy coating remains indistinguishable from that for the Zn-55Al-Si coating of similar thickness in tidal zone, and is two to three times lower than the latter in immersion zone. The decrease in tensile strength suggested that galvanized and Zn-55Al-Si coated steel suffer intense pitting corrosion in immersion zone. The electrochemical tests showed that all these coatings provide cathodic protection to the substrate metal; the galvanic potentials are equal to - 1,050, - 1,025 and - 880 mV (SCE) for zinc, Zn-25Al alloy and Zn-55Al-Si coating, respectively, which are adequate to keep the steel inside the immunity region. It is believed that the superior performance of the Zn-25Al alloy coating is due to its optimal combination of the uniform corrosion resistance and pitting corrosion resistance. The inferior corrosion performance by comparison of the Zn coating mainly results from its larger dissolution rate, while the failure of the Zn-55Al-Si coating is probably related to its higher susceptibility to pitting corrosion in seawater.

Diet shift of upland buzzards (Buteo hemilasius): evidence from stable carbon isotope ratios

We measured the stable carbon isotope ratios for muscle of the upland buzzards (Buteo hemilasius), plateau pika (Ochotoma curzoniae), root vole (Microtus oeconomus), plateau zokor (Myospalax fontanierii) and passerine bird species at the Haibei Alpine Meadow Ecosystem Research Station (HAMERS), and provided diet information of upland buzzards with the measurement of stable carbon isotopes in tissues of these consumers. The results showed that δ~(13)C values of small mammals and passerine bird species ranged from -25.57‰ to -25.78‰ (n = 12), and from -24.81‰ to -22.51% (n = 43), respectively, δ~(13)C values of the upland buzzards ranged from -22.60‰ to -23.10‰ when food was not available. The difference in δ~(13)C values (2.88‰±0.31‰) between upland buzzards and small mammals was much larger than the differences reported previously, 1‰-2‰, and showed significant difference, while 1.31‰±0.34‰ between upland buzzard and passerine bird species did not differ from the previously reported trophic fractionation difference of 1‰-2‰. Estimation of trophic position indicated that upland buzzards stand at trophic position 4.23, far from that of small mammals, i.e., upland buzzards scarcely captured small mammals as food at the duration of food shortage. According to isotope mass balance model, small mammals contributed 7.89% to 35.04% of carbon to the food source of the upland buzzards, while passerine bird species contributed 64.96% to 92.11%. Upland buzzards turned to passerine bird species as food during times of shortage of small mammals. δ~(13)C value, a useful indicator of diet, indicates that the upland buzzards feed mainly on passerine bird species rather than small mammals due to "you are what you eat" when small mammal preys are becoming scarce.

青海省生态环境治理面临的问题与草业科学的发展

青海省生态环境恶化的主要特征是 :草地退化 ,水土流失 ,土地沙化 ,冰川湿地退缩 ,自然灾害频繁 ,人畜饮水困难 ,农村能源短缺。当前生态环境治理面临着试验示范不够、缺少治理规划、种苗供应混乱、资金投入不够等问题 ,需要加强治理规划工作和技术支撑体系、建立生态环境治理责任制、紧密结合生产结构调整及草产业的发展等方面开展工作。需要依据草业科学的原理 ,在生态环境治理中重视生态工程设计的应用 ,对治理区按照草地农业系统四个生产层次统筹考虑优化生产结构 ,发挥各系统和层次间的耦合效应。生态环境治理面临的问题为草业科学原理的实践及发展提供了广阔的天地。

CIM系统设计中的关键问题

虽然新的制造系统不断涌现 ,企业仍然对CIM给予很大广泛的认可。本文讨论了CIM设计中的一些关键问题。首先 ,根据业务过程重组来实施CIM至关重要 ,其次 ,必须采用CIM的功能体系结构规范和容纳各种功能系统 ,以便更好地执行业务流过程。同时 ,需要有相应的集成基础结构来支持整个企业的数据管理。

制造系统的可重构性

可重构制造模式是一种指导管理和控制制造系统重构过程的制造哲理 ,它使制造系统有效地响应不断变化的环境。制造系统具有可重构能力是其生存和发展的基本手段 ,具有较高可重构性的公司在风云突变的环境中将远远超过其竞争对手。本文探讨了可重构制造模式的基本定义和内涵 ,并从组织、过程、产品、加工系统和信息平台等五个方面研究了制造系统的可重构性。

供应链中物流及信息流管理

供应链管理使企业在变化的市场环境中有效地与其它企业合作 ,取得集体竞争优势。本文首先讨论了后勤学与供应链管理的定义和之间的关系。本文认为供应链管理的核心是物流与信息流的控制。物流控制决策主要包括操作层次的库存补充和运输路径规划 ,以及战略层次的设施地点规划。信息流管理跨越部门与企业的界限将相关的应用集成起来。动态联盟协调各企业内部的生产经营活动 ,战略性地决定物流与信息流的构形。

氢氧化铁胶体/水界面作用与地表水中稀土元素的分异—— pH控制机理的实验研究

实验研究了pH对REE水/粒界面配分行为的影响: 氢氧化铁胶体对REE的作用在胶体形成开始以吸附为主, 然后是解吸, 最后是吸附/解吸趋向平衡; 轻稀土元素(LREE)和重稀土元素(HREE)的吸附率不同, 后者大于前者. 随pH增加, LREE和HREE在氢氧化铁胶体/水之间产生分异, 其配分系数比值(DLREE/DHREE)降低; DREE的分布模式呈现Y的异常(DY/DHo<1)并在低pH条件下呈现明显的四重效应. 实验结果证明自然界中存在REE四重效应. 除pH外, 地表水的化学类型以及离子强度也是控制REE四重效应以及微粒吸附态REE和溶解态REE之间产生分异的重要因素.