BIOSORPTION OF PRECIOUS AND HEAVY METALS*

The biosorption of metals has already attracted a great deal of attention because of its application potential in environment protection and removal or recovery of precious and heavy metals. The research activities about biosorption of precious and heavy metal ions by the biosorbent, the biomass of microorganisms, plants and animals for deriving, was described in this paper. The mechanisms of biosorption were also reviewed. Ref 33国家自然科学基金资助项目 (No .2 98760 2 6)~

中期妊娠两种药物引产方法的比较

目的　探索中期妊娠引产的方法。方法　将要求引产的 10 1例健康孕妇 ,随机分为两组。服药组 5 0例 ,140天者 ,米非司酮 30 0mg ,2次 /日 ,均空腹口服。第 3天晨口服米索前列醇 6 0 0 μg ,视宫缩及宫颈张开情况每 6小时阴道后穹窿放置米索 5 0 - 2 0 0 μg ,总量≤ 12 0 0 μg。注射组 5 1例 ,羊膜腔内注射利凡诺 10 0mg。 结果　两组引产成功率和产后出血量无差异 ,但服药组胎盘胎膜残留率显著低于注射组 (P <0 .0 1)。结论　大剂量米非司酮配伍米索用于中期妊娠引产方法简便 ,安全可靠 ,有推广价

The Experimental Study on Flow Boiling Heat Transfer of Working Fluid R245fa in Horizontal Tube

设计了管内沸腾换热系数及总传热系数测定试验台架,对R245fa工质在内径6 mm水平光管内的流动沸腾换热特性进行试验研究。测试质流密度为50 ~; 150 kg /(m~2·s),工质蒸发温度为50, 60和70℃。结果表明:; 随着工质含汽率的增加,R245fa的流动沸腾换热系数呈先增大后降低趋势。对于304不锈钢套管式换热器,烟气与R245fa工质进行换热的总传热系数; 约在40 ~ 65 W/(m~2·K) 。A bench - scale facility was designed for testing the flow boiling heat; transfer coefficient and the total heat transfer coefficient. The; boiling heat transfer characteristics of the R245fa refrigerant were; studied in a horizontal smooth tube with 6 mm inner diameter. The; parameters investigated were mass flow rate (50 ~ 150 kg /(m~2·s)),; evaporation temperature (50, 60 and 70 ℃). The results showed that the; flow boiling heat transfer coefficient of R245fa increased with the; increase of rate of vapor content, and decreased slightly with the; further increase of rate of vapor content. The total heat transfer; coefficient of the flue gas and the R245fa is about 40 ~ 65 for the 304; stainless steel heat exchanger.国家国际科技合作专项资助项

The Accountability of the Offshore Drilling Platform’s Oil Pollution Damages in the COPC Incident

*张丽英,中国政法大学国际法学院教授,副院长,博士生导师,中国海事仲裁委员会仲裁员,中国海商法协会常务理事。电子邮箱:[email protected]。 **刘佳,中国政法大学国际法学院研究生。电子邮箱:[email protected]。［文摘］渤海湾蓬莱19-3油田溢油事件引起了广泛关注,如何追究相关责任方的油污损害责任成为当务之急,但责任追究之路的重重困难使我国海上钻井平台油污损害责任追究相关法律和制度的不足日益凸显,包括责任主体不明、请求主体不全面、赔偿范围模糊不清、处罚力度过低等问题。反观美国墨西哥湾漏油事件,其处理的及时和赔偿的到位值得我们借鉴。本文在比较美国墨 西哥湾漏油事件及美国相关国内法的基础上,认为我国应在建立健全相关法律法规,明确具体地规定不同污染来源时的对应责任主体,扩大请求主体和赔偿范围,提高责任限额等方面进行改进。［Abstract］The Bohai Bay oil spill has brought to the fore certain issues concerning the assignment of liability to parties involved in offshore environmental damages.The incident has highlighted weaknesses in China’s current system of accountability in offshore oil drilling,namely ambiguous definition of responsible party,incomplete range of claimants,vague scope of compensation and lax administrative punishment.The U.S. Gulf of Mexico oil spill and its aftermath,by contrast,demonstrated elements of an effective legal response to a similar environmental incident,specifically with respect to liability and compensation,and can therefore serve as an instructive case study in efforts to advance the Chinese offshore drilling legal regime.After comparing the two aforementioned incidents and the respective legal lessons learned therein,the authors conclude that elucidating the process of identifying responsible parties,expanding the scope of compensation,and increasing liability limits are necessary actions for improving the efficacy and efficiency of relevant Chinese laws

Study on Chemical Mutation of Selected Strain of Saccharomyces Carlsbergensis FB

通过EMS诱变,从啤酒酿造生产菌株啤酒酵母(Saccharomyces carlsbergensis)FB中筛选分离得到一株发酵液中双乙酰含量优于亲株的新菌株FB-E1。以120Bx麦芽汁为培养基,用内装300ml麦芽汁的500ml三角瓶于12℃下发酵,发酵8d后发酵液中双乙酰含量比亲株降低了42.7%。该菌株的其它发酵性能的测定结果表明其保持了亲株的优良性状,且遗传性状稳定。After mutation with EMS (ethyl methane sulfonate), a Saccharomyces carlsbergensis strain FB-E1 was selected fromoriginal strain FB, a strain for beer brewage production. The diacetyl content in the fermented liquid during the fermentation wasinvestigated in 500ml flask with 300ml 120Bx wort at 11℃. After 8d, the diacetyl content in the fermented liquid of FB-E1 was0.0706mg/L, 42.7% lower than that of its original strain A (0.1233mg/L). The results showed that flocculence and fermentationrate of strain FB-E1 were kept just as good as the original strain FB

端面泵浦Nd∶YAG连续输出1052nm波长激光器

设计了一个简单紧凑的1052nm波长激光器。首次利用激光二极管(LD)端面泵浦Nd∶YAG晶体,使用镀有高度选择性介质膜的反射镜产生该波段的激光。激光阈值为0.3W,当808nm波长泵浦光功率达到18W时产生了3.5W的1052nm波长激光输出。光-光转换效率为20%,输出激光功率波动不超过3%

Lithium Storage Performance of Hard Carbons Anode Materials Prepared by Different Precursors

以聚丙烯腈、石油沥青和花生壳为前驱体,在1200℃下碳化制备三种不同的硬碳材料。通过扫描电子显微、X射线衍射、氮气吸附/脱附测试和拉曼光谱等方法探究不同前驱体所制备的硬碳材料的表面形貌和物相结构。通过恒流充放电测试考察了这三种硬碳负极材料的电化学性能。结果表明,花生壳基硬碳的初始放电比容量最高,但首圈库仑效率最低,石油沥青基硬碳的首圈库仑效率最高但是比容量最低,聚丙烯腈基硬碳具有较高的循环比容量和稳定性。Hard carbon is one of the most promising anode material for lithium ion batteries (LIBs) owing to its high stability, widespread availability, low-cost, and excellent performance. The electrochemical properties of hard carbon materials depend strongly on the type of precursors. It is, therefore, very important to choose an excellent hard carbon precursor. Polyacrylonitrile, petroleum pitch and peanut shells were used as raw materials to prepare different hard carbon anode materials for LIBs. These hard carbon anode materials were successfully synthesized in two steps. The selected precursor was firstly carbonized at 600℃ for 1 h in argon atmosphere using heating rate of 1℃·min-1, and then was further carbonized at 1200℃ for 1h in argon atmosphere using heating rate of 5℃·min-1. Under such a low heating rate, a relatively small specific surface area could be obtained as much as possible for the hard carbon anode material. The surface morphology and phase structure of as synthesized hard carbon materials were analyzed by scanning electron microscopy, X-ray diffractometer, nitrogen adsorption analyzer and Raman spectrometer. The ion carrier storage mechanism was further investigated using cyclic voltammetry by examining whether the ion insertion/extraction mechanism is surface-controlled pseudocapacitance or diffusion-limited intercalation. It was further verified that the lithium storage mechanism of hard carbon anode materials is in line with the “adsorption-intercalation” mechanism. The results indicated that polyacrylonitrile-derived hard carbon anode material had low impedance by EIS test. This may be the reason why the low voltage platform of polyacrylonitrile-derived hard carbon materials had a higher specific capacity. The electrochemical performance of different hard carbon materials were investigated through galvanostatic charge and discharge tests. The peanut shell-derived hard carbon material showed the highest initial specific capacity (579.1 mAh·g-1), but the lowest initial coulombic efficiency (49.35%). The petroleum pitch-derived one delivered the highest initial coulombic efficiency (85.97%), but the lowest initial specific capacity (301.7 mAh·g-1). Comparing the cycle performance of these three hard carbon materials, polyacrylonitrile-derived hard carbon materials exhibited the excellent cycling performance (87.17% of capacity over 500 cycles). This study would provide useful assistance to understand the precursor-derived electrochemical properties of hard carbon anode material in practical applications.国家自然科学基金面上项目(21673051);广东省科技厅国际合作项目资助(2019A050510043);广东省科技厅产学研重大专项(2017B010119003)通讯作者:施志聪E-mail:[email protected]:Zhi-CongShiE-mail:[email protected]广东工业大学材料与能源学院,新能源材料与器件系,广东 广州 510000Department of New Energy Materials and Devices, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510000, Guangdong, Chin

ST段抬高型急性心肌梗死院前溶栓治疗中国专家共识

急性心肌梗死仍然严重威胁我国人民健康,在我国广大城乡地区,形势更为严峻[1,2]。及时救治急性心肌梗死患者,降低死亡率和保护心脏功能刻不容缓。鉴于我国的实际情况,院前溶栓治疗在大城市以外的城乡地区具有重要意义。为此,中国医师协会胸痛专业委员会及中国医学救援协会心血管急救分会专门组织有关专家制订了本共识,旨在帮助院前医疗急救人员对急性心肌梗死患者选择最佳

秸秆组分分离及其高值化转化的研究

秸秆的高值化转化是一世界性难题，而组分分离是高值转化的基础。因此本文以秸秆组分分离为研究重点，首先建立了玉米秸秆组分的近红外光谱清洁快速分析方法；然后对玉米秸秆的不均一性进行了研究，并在此基础上，建立了玉米秸秆的纤维束组织和杂细胞组织的分离方法；第三探讨了离子液体用于秸秆组分分离的可行性。 针对现有的秸秆组分分析方法复杂、污染成本高等缺点，以改进的秸秆化学分析方法——滤袋分析技术为化学分析依据，首次建立了我国玉米秸秆的近红外光谱数据库和玉米秸秆六大组分（灰分、半纤维素、纤维素、Klason木素、酸不溶灰分和水分）的近红外快速测定模型，模型的相关系数在0.86以上，预测误差<2.58%，可以满足我国玉米秸秆组分快速测定的需要。 针对秸秆整株利用价值低的问题，对玉米秸秆的不均一性进行了研究。结果发现，玉米秸秆不同部位的组成和结构存在很大差异，皮和叶的结构致密，芯的结构比较疏松，各部分在秸秆中所占的重量比例也不同，而且随着秸秆直径的变化而变化。从化学组成来看，皮中的纤维素含量最高（36.66%），与其它各部位的纤维素含量差异显著；叶中的半纤维素含量最高（33.86%）；而木质素主要集中在皮和结，含量分别为14.23%和12.52%，两者差异显著与其它各部位也差异显著；灰分则主要集中在叶部（11.63%），与其它各部位差异显著。从细胞组成来看，皮中的杂细胞含量最少为50%，叶和芯中的杂细胞分别为60%和70%（面积比）。这种结构的不均一性导致了各部位的酶解率的不均一性，芯的酶解率最高，酶解24 h后可达88.32%，而相同条件下叶的酶解率为28.33%。不同部位的纤维特征也不一致，在皮和叶中存在与木材纤维特征相近的优质纤维。因此，有必要对不同部位的组织进行分离，实行分步转化。 针对上述秸秆的不均一性研究结果，建立了秸秆的蒸汽爆破——机械梳理组织分离技术，实现了秸秆中优质纤维与杂细胞组织的分离。不同部位的汽爆条件不同，其中皮为1.5Mpa， 7min，梳理时的物料水分含量为30%。分离得到的纤维束组织利于制浆，浆得率可达65%，浆白度在60%以上。分离得到的杂细胞更易于发酵，采用绿色木霉发酵生产纤维素酶，最高酶活可以达到194.18 FPU/g干曲。说明不同组织的利用性能不同，组织分离利于实现高值转化。 离子液体氯化1-丁基-3-甲基-咪唑（[BMIM]Cl）是一种绿色溶剂，因此探讨了它对秸秆组分分离和酶解发酵的影响。研究证明，[BMIM]Cl也可通过破坏半纤维素之间的氢键溶解半纤维素，但[BMIM]Cl对大分子木质素不溶，因此可以实现木质素的分离。[BMIM]Cl能使纤维素酶不可逆失活，但经离子液体处理后的汽爆秸秆具有良好的酶解和发酵性能，酶解率可以达100%，纤维素酶酶活可达118.64 FPU/ g 干曲。利用离子液体的纤维素溶液可进行再生纤维素膜的制备，膜具有良好的力学性能和水通量。离子液体可回收重复使用，是一种良好的纤维素溶剂，具有工业应用价值

离子液体在生物催化中的应用

近年来, 离子液体 (ILs) 以其独特的优势成为生物催化反应研究的热点, 尤其是作为生物催化反应的溶剂或共溶剂的研究更是备受关注. 许多酶能在 ILs或其形成的两相体系或单相体系中保持催化活性. 如目前研究最多的脂肪酶, 有多种能在 ILs中表现出活性稳定、反应选择性提高、产率提高等优良特性; 某些蛋白酶在ILs中稳定性提高, 具有酯酶的活性; &beta; 半乳糖苷酶在 ILs中的催化产率提高; 全细胞在 ILs中的催化反应效果也较好; 但是也有某些酶, 如纤维素酶、某些过氧化物酶等在 ILs中活性会降低或丧失. 因此有关这一方面的研究还有待进一步深入