中国制造还具有劳动力成本优势吗

本文利用2002—2011年的制造业数据核算比较了我国与主要竞争国家的制造业单位劳动力成本,发现我国单位劳动力成本已经高于印尼、泰国和马来西亚等东南亚国家。具体地,我国东部地区单位劳动力成本2002年以后高于印尼,2007年超过中西部地区和泰国,2011年超过马来西亚;中西部地区单位劳动力成本2002年以后高于印尼,2009年超过泰国,2011年超过马来西亚,其主要原因在于我国小时劳动力成本上升过快。与印尼、泰国、马来西亚等东南亚国家相比,我国已不具有劳动力成本优势,再加上近年来我国人口红利的消失,中西部地区劳动力成本也已高于东南亚国家,因而,可以解释我国中西部地区为何没能及时接收东部地区的产业转移。中央高校基本科研业务费专项资金项目“中国经济结构转型中若干问题探析”(20720171027)的资

The beauty of glass——Philip Johnson's three glass building

在菲利普约翰逊的一生中设计了众多的流派和风格的建筑,而他对玻璃这种建筑材料的使用贯穿了他的整个建筑生涯。由于他对建筑形式和建造法则的理解一直在变化中,他的作品也一直处于变化中,通过探究他对玻璃的这种单一材质在不同建筑中的运用,总结约翰逊的建筑哲学和他对建筑本源的思考,从而对建筑设计产生新的认知。Philip Johnson designed many genres and styles of architecture in his lifetime,and in glass was used as building materials throughout his entire architectural career.His architecture work has been in flux,because he thought that the rules of architectural forms and construction has been changing.Through exploring glass the single material used in his different buildings to summary Johnson's architectural philosophy or his thinking on the building origin,and to generate new cognition on architectural design

Commercial development mode of exploration——Garden King Street Conceptual Design

近年来,现代商业正如火如荼的发展,商业模式创新已成为建筑设计行业的一个热点。一个合理的开发模式不仅对建筑设计行业有着长远的意义而且对和谐社会环境的发展也有着重要的作用。本文通过“花园式“金街概念设计,旨在探索一种合理的商业开发模式,这种模式适用于南北各地,在不同地区有着不同的建筑表达。In recent years,the development of modern business is in full swing,business model innovation has become a hot topic of architectural design industry.A rational development model not only for the architectural design industry has a long- term significance but also for the development of a harmonious social environment also has an important role.In this paper,a " garden- style" Golden Street concept designed to explore a reasonable business development model that applies throughout North and South,in different regions have different architectural expression.In this paper,theoretical literature survey and computer simulation designed to explore a reasonable development in the Chinese business model

教育扩招、人力资本与企业创新

本文以1999年实施的教育扩招政策作为准自然实验,利用双重差分策略(DID)考察了非R&D投入——人力资本对企业创新的影响。研究发现,人力资本促进了企业创新数量和创新质量上升:人力资本密集...中央高校基本科研业务费专项资金项目“中国经济结构转型中若干问题探析”(20720171027);; 国家留学基金的资

Flooding Efficiency of Flooding systems and Wettability Study on the Simulaitn Rock Surface

为了研究驱油体系在模拟岩芯表面的润湿性，为微重力应用研究提供依据，选择胜利纯梁采油厂c6—41井原油，应用正交实验设计，通过最低瞬时界面张力测定，筛选出阴离子表面活性剂sDc—V、非离子表面活性剂FBB、HPAM和复碱的驱油体系配方．开展室内模拟驱油实验，同时测定驱油体系溶液对模拟岩芯的接触角，并且关联驱油效率和接触角之间的关系，发现驱油效率越高，接触角值越小

Preparation of biochars from biogas residue and adsorption of ammonia-nitrogen in biogas slurry

以生物产甲烷的副产物沼渣为原料,用5种不同的方法通过化学活化法制备生物炭,实验结果表明5种生物炭对沼液中的氨氮都有吸附效果,而氢氧化钾活化制备的生物炭(kOH-CC)对氨氮的吸附效果相对较好,吸附剂对氨氮的吸附符合准二级吸附动力学,吸附等温线表现为lAngMuIr型,通过拟合计算最大吸附容量能达到120 Mg·g-1。对生物炭进行bET、扫描电镜及红外等表征,分析了kOH-CC生物炭吸附氨氮过程的作用机理。Five types of biochars were prepared through chemical activation utilizing fermentation residue from biogas plants.NaOH, KOH, H2SO4, H3PO4 and ZnCl2 were used as chemical activating agents.Biochars could absorb ammonia-nitrogen in biogas slurry.Biochar derived from KOH treatment(KOH-CC) showed better adsorption efficiency than the others.The adsorption process followed pseudo-second-order kinetics, and the adsorption isotherm could be fitted to Langmuir equation.Simulation test indicated that the maximum adsorption capacity could reach 120 mg·g-1.The properties of KOH-CC were characterized by BET, SEM, XRD and FTIR.The machanism of ammonia-nitrogen adsorption was discussed.国家重点基础研究发展计划项目(2013CB733505)~

BP神经网络和ARIMA模型对污水处理厂出水总氮浓度的模拟预测

污水处理厂出水总氮(TN)浓度是评价水处理效果的关键指标之一,利用BP神经网络建立模型对污水处理厂脱氮工艺进行模拟,引入自回归移动平均模型(ARIMA)对污水处理厂未来短期出水TN浓度进行预测..

BP神经网络和ARIMA模型对污水处理厂出水总氮浓度的模拟预测

污水处理厂出水总氮(TN)浓度是评价水处理效果的关键指标之一。建立BP神经网络模型对污水处理厂脱氮工艺进行模拟,引入自回归整合移动平均模型(ARIMA模型)对污水处理厂未来短期出水TN浓度进行预测。结果表明:BP神经网络模型在训练集和测试集模拟结果的平均相对误差分别为15. 9%和16. 5%,模型预测结果的平稳性较差; ARIMA模型对未来7 d出水TN浓度的时序预测平均误差为4. 41%,预测精度较高; 2个模型相结合有助于实现污水处理厂快捷和高效的在线检测。福建省自然科学基金项目(2018J01016);;\n厦门大学大学生创新创业训练计划项目(2018X0256

Preparations and Electrocatalytic Ethanol Properties of Palladium Intercalated Hydrotalcite

高性能的电催化剂对直接燃料电池的商业化应用有着至关重要的作用,目前的阳极材料还存在活性低、易中毒、成本高等问题。本研究以层状双氢氧化物(layered double hydroxides, LDHs)为载体通过浸渍法制备了新型纳米钯(Pd)催化剂,并通过X射线衍射仪、扫描电子显微镜、电感耦合等离子体质谱仪、能谱仪、透射电子显微镜、循环伏安法测试、计时电流测试和电化学阻抗等方法对催化剂的结构和电催化性能进行了研究。结果表明,新制备的Pd/Mg-Al-LDHs仍然保持着LDHs的层状结构,循环伏安测试表明在碱性条件下,Pd/Mg-Al-LDHs比Pd/C有更好的电催化乙醇活性和抗中间产物中毒性能,且乙醇浓度、扫描速率和温度等因素对峰电流有着直接影响。计时电流测试表明在电催化乙醇的过程中Pd/Mg-Al-LDHs比Pd/C拥有更高的电催化活性和稳定性。电化学阻抗测试表明,Pd插层可显著改善Mg-Al-LDHs的导电性,并降低电催化过程中电荷转移阻力。High-performance electrocatalysts play a vital role in the commercial application of direct fuel cells. Current anode materials still have such problems as low activity, easy poisoning and high cost. In this study, a new type of nano- palladium (Pd) catalyst was prepared by dipping method using layered double hydroxides (LDHs) as the carrier. X-ray diffractometer, scanning electron microscope (SEM), inductively coupled plasma mass spectrometer (ICP-MS), energy spectrometer, transmission electron microscope (TEM), cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscope were used to analyze the structure and electrocatalytic performance of the catalyst. The results showed that the newly prepared Pd/Mg-Al-LDHs still maintained the layered structure of LDHs, and the metal Pd was evenly dispersed between the layers of hydrotalcite. Cyclic voltammetric curves showed that under alkaline conditions, the peak current density of Pd/Mg-Al-LDHs with 7% Pd in electrocatalytic ethanol was 36 mA·cm-2. The peak current density of commercial Pd/C in electrocatalytic ethanol was 30 mA·cm-2, and Pd/Mg-Al-LDHs exhibited better resistance to intermediate product poisoning. The factors including ethanol concentration, scanning rate and temperature were found to be effective, in particular, peak current had a direct effect. The chronoamperometric test revealed that Pd/Mg-Al-LDHs displayed higher electrocatalytic activity and stability toward ethanol than Pd/C, and the current density of Pd/Mg-Al-LDHs at 2000 s was 12 times to that of the commercial Pd/C. The electrochemical impedance data showed that Pd intercalation could significantly improve the conductivity of Mg-Al-LDHs and reduce the resistance to charge transfer during the electrocatalytic process.国家自然科学基金项目(51208299)通讯作者:李亮E-mail:[email protected]:LiangLiE-mail:[email protected]上海理工大学环境与建筑学院,上海 200093School of Environment and Architecture,University of Shanghai for Science and Technology, Shanghai 200093, Chin

中国海及邻近区域碳库与通量综合分析

中国海总面积约470万平方公里,纵跨热带、亚热带、温带、北温带等多个气候带.其中,南海北依\"世界第三极\"青藏高原、南邻\"全球气候引擎\"西太平洋暖池,东海拥有全球最宽的陆架之一,跨陆架物质运输显著,黄海是冷暖流交汇区域,渤海则是受人类活动高度影响的内湾浅海.中国海内有长江、黄河、珠江等大河输入,外邻全球两大西边界流之一的黑潮.这些鲜明的特色赋予了中国海碳储库和通量研究的典型代表意义.文章从不同海区（渤海、黄海、东海、南海）、不同界面（陆-海、海-气、水柱-沉积物、边缘海-大洋等）,以及不同生态系统（红树林、盐沼湿地、海草床、海藻养殖、珊瑚礁、水柱生态系统等）多层面对海洋碳库与通量进行了较系统地综合分析,初步估算了各个碳库的储量与不同碳库间的通量.就海气通量而言,渤海向大气中释放CO2约0.22Tg Ca-1,黄海吸收CO2约1.15Tg Ca-1,东海吸收CO2约6.92～23.30Tg Ca-1,南海释放CO2约13.86～33.60Tg Ca-1.如果仅考虑海-气界面的CO2交换,中国海总体上是大气CO2的\"源\",净释放量约6.01～9.33Tg Ca-1.这主要是由于河流输入以及邻近大洋输入所致.河流输入渤黄海、东海、南海的溶解无机碳（DIC）分别为5.04、14.60和40.14Tg Ca-1,而邻近大洋输入DIC更是高达144.81Tg Ca-1,远超中国海向大气释放的碳量.渤海、黄海、东海、南海的沉积有机碳通量分别为2.00、3.60、7.40、7.49Tg Ca-1.东海和南海向邻近大洋输送有机碳通量分别为15.25～36.70和43.39Tg Ca-1.就生态系统而言,中国沿海红树林、盐沼湿地、海草床有机碳埋藏通量为0.36Tg Ca-1,海草床溶解有机碳（DOC）输出通量为0.59Tg Ca-1;中国近海海藻养殖移出碳通量0.68Tg Ca-1,沉积和DOC释放通量分别为0.14和0.82Tg Ca-1.总计,中国海有机碳年输出通量为81.72～103.17Tg Ca-1.中国海的有机碳输出以DOC形式为主,东海向邻近大洋输出的DOC通量约15.00～35.00Tg Ca-1,南海输出约31.39Tg Ca-1.综上,尽管从海-气通量看中国海是大气CO2的\"源\",但考虑了河流、大洋输入、沉积输出以及微型生物碳泵（DOC转化输出）作用后,中国海是重要的储碳区.需要指出的是,文章数据是基于中国海各海区碳循环研究报道,鉴于不同研究方法上的差异,所得数据难免有一定的误差范围,亟待将来统一方法标准下的更多深入研究和分析.国家重点研发计划项目(编号:2016YFA0601400);;国家自然科学基金项目(批准号:91751207、91428308、41722603、41606153、41422603);;中央高校基础研究项目(编号:20720170107);;中海油项目(编号:CNOOC-KJ125FZDXM00TJ001-2014、CNOOCKJ125FZDXM00ZJ001-2014)资