Pore-Scale Investigation of Coupled Two-Phase and Reactive Transport in the Cathode Electrode of Proton Exchange Membrane Fuel Cells

A three-dimensional multicomponent multiphase lattice Boltzmann model(LBM) is established to model the coupled two-phase and reactive transport phenomena in the cathode electrode of proton exchange membrane fuel cells.The gas diffusion layer(GDL) and microporous layer(MPL) are stochastically reconstructed with the inside dynamic distribution of oxygen and liquid water resolved,and the catalyst layer is simplified as a superthin layer to address the electrochemical reaction,which provides a clear...     

A systematic review： How to choose appropriate health-related quality of life （HRQOL） measures in routine general practice？

INTRODUCTION The ultimate goal of health care is to maintain or improve the quality of life of people. Health is an important determinant of a person’s quality of life although it is not the only one. Other factors such as culture, religion, environment, education and finance can also affect quality of life but they are often be- yond the scope of health care. Health-related quality of life (HRQOL) is the main concern of health care professionals and is becoming an important health out…     

Pretreatment of coking wastewater using anaerobic sequencing batch reactor （ASBR）

INTRODUCTION Coking wastewater is generated in the produc- tion of coke, coal gas, tar and other coke by-products The coking wastewater includes inorganic pollutants such as ammonia, cyanogen, sulfocyan, heterocycle compounds and polycyclic aromatic compounds such as phenol, oils, naphthalene, pyridine, quinoline and anthracites, which are difficult to biodegradation under aerobic conditions (Ganczarczyk, 1972). Dis- charge of coking wastewater to the environment may cause severe contamin…     

基于DSP的超声风速测量

设计了超声波发射、接收、放大等电路,采用高速A/D转换器采集超声波接收信号,利用DSP进行数据处理.设计IIR带通滤波器对采集信号进行前后向滤波以消除延迟,通过窄带及宽带滤波分别取得序列A与B.利用序列A通过插值取得首先超过阈值的某一周期的精确起始时间,通过序列A及反相序列A′分别与序列B的对应周期进行方差分析,利用假设检验来识别接收波形的起始周期,从而求出超声波的传输时间.通过超声波在三坐标轴向来回的传输时间与空气流速间的关系,求出三维风速与风向.结果表明,测量可靠性及精度得到提高,电路设计也得到简化.     

How Chinese Teach Mathematics: Canadian Teachers’ Perspectives

As part of a large reciprocal learning partnership project between Canada and China, this study explored Canadian teachers’ perceptions of mathematics teaching in elementary schools in China. Using reciprocal learning and Activity Theory as the theoretical lens, we collected data, i.e., classroom observations, group discussion, and informal exchanges from teachers in a pair of research sister-schools in Canada and China. Qualitative data analyses revealed four themes in Canadian teachers’ perceptions of the characteristics of Chinese mathematics teaching: an active teacher-student interaction model of questioning-responding, a mathematical knowledge-package summary at the end of each lesson, integration of the history of mathematics into teaching, and the development and implementation of well-structured lessons. Contributions, implications, and limitations of the study in mathematics education and research are discussed.     

采用气质联用技术和高效液相色谱对布朗山古树普洱晒青茶挥发性成分和生物活性成分进行比较分析（英文）

目的:为布朗山不同品种古树普洱晒青茶香气物质和活性成分(多酚类和咖啡碱)深入研究提供理论依据.创新点:首次采用气质联用技术(GC-MS)和高效液相色谱(HPLC)结合化学计量学对布朗山不同品种的古树普洱晒青茶进行研究,探究不同品种古树晒青茶成分之间的差异性.方法:采用顶空固相微萃取法(HS-SPME)结合GC-MS对香气成分进行鉴定;采用70%甲醇溶液对活性成分进行富集,使用HPLC进行分析;结合主成分分析(PCA)和偏最小二乘判别分析(PLS-DA)对不同品种的古树普洱晒青茶进行区分并对区分起主要作用的物质进行筛选.结论:三个品种的古树普洱晒青茶(老曼峨、老班章和布朗)香气成分组成及含量差异较大,但主要成分均为醇类、碳氢类和酮类化合物.老曼峨中多酚类化合物含量较高,其次为布朗和老班章,相比于多酚类,咖啡碱含量表现出了相反的趋势.相比于PCA分析,PLS-DA分析对三个品种的古树普洱晒青茶均显示出了较好的区分效果.变量投影重要性准则(VIP)分析结果显示34种香气和5种生物活性成分对不同品种的古树普洱晒青茶区分贡献较大.     

Advanced primary peritoneal carcinoma： clinicopathological and prognostic factor analyses

Objective: To investigate the factors favoring a positive prognosis for advanced primary peritoneal carcinoma (PPC). Methods: Twenty-four cases meeting the criteria for PPC were analyzed retrospectively for the clinicopathologic profiles. Immunohistochemistry was used to determine the expressions of p53, Top2α, Ki-67 and Her-2/neu. Then all these clinicopathological factors and molecular markers were correlated with the prognosis. Results: There were 15 cases of primary peritoneal serous papillary carcinoma (PPSPC), 6 cases of mixed epithelial carcinoma (MEC) and 3 cases of malignant mixed Mullerian tumor (MMMT). All patients underwent cytoreductive surgery with optimal debulking achieved in 3 cases. Among those receiving first-line chemotherapy, 13 patients received the TP regimen (paclitaxel-cisplatin or carboplatin) and 7 patients received the PAC regimen (cisplatin-doxorubicin-cyclophosphamide). The median overall survival of all patients was 42 months, while the breakdown for survival time for patients with PPSPC, MMT and MEC was 44, 13 and 19 months, respectively. The expressions of p53, Top2a and Ki-67 were all demonstrated in 11 cases respectively. None showed the expression of Her-2/neu. There were significant differences in the median survival between patients with PPSPC and those with MMMT (44 months vs 13 months, P<0.05), also between patients receiving TP combination and those receiving the PAC regimen (75 months vs 28 months, P<0.05). Another significant difference in the median progression-free survival (PFS) was identified between patients with positive p53 immunostaining and those with negative p53 immunostaining (15 months vs 47 months, P<0.05), whereas age, menopausal status, residual tumor size and the other molecular factors did not significantly impact survival. Conclusion: Patients with PPC should be treated with a comprehensive management plan including appropriate cytoreductive surgery and responsive chemotherapy. Overestimating an optimal debulking surgery may not benefit survival. The pathologic subtype, chemotherapy regimen and p53 overexpression were significant prognostic factors.     

Spatio-temporal expression of the pathway-specific regulatory gene redD in S. coelicolor

INTRODUCTION Streptomycetes are gram-positive soil bacteriarenowned for their ability to produce a large numberof different secondary metabolites. Their life cycleinvolves complex morphological differentiation,which is believed to be closely co-ordinated with geneexpression that promotes a variety of physiologicaland structural changes including the onset of antibi-otic biosynthesis. S. coelicolor has been extensivelystudied as a model system with the aid of genetic andmolecular technique…     

DEVELOPMENT OF A VACUUM SPARK DISCHARGE SOURCE

ＤＥＶＥＬＯＰＭＥＮＴＯＦＡＶＡＣＵＵＭＳＰＡＲＫＤＩＳＣＨＡＲＧＥＳＯＵＲＣＥＤＥＶＥＬＯＰＭＥＮＴＯＦＡＶＡＣＵＵＭＳＰＡＲＫＤＩＳＣＨＡＲＧＥＳＯＵＲＣＥ￥ＧｕｏＹｕ－ｂｉｎ；ＬｉＦｕ－ｔｉａｎ（ＣｈａｎｇｃｈｕｎＩｎａｔｉｔｉｄｅｏｆＯｐｔｉ...