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New Journal of Glass and Ceramics 2021年第2期11卷 45-56页

作者： Gomaa el Damrawi Rawya Mhammed Ramadan Mohamed el Baiomy Glass Research Group Physics Department Faculty of Science Mansoura University Mansoura Egypt Microwave Physics and Dielectrics Department Physics Research Division National Research Centre Cairo Egypt

Glasses in the system 24.5Na2O·24.5caO·6P2O5·xSrO·(45-x)SiO2 have been studied in the composition region of x = 0 - 15 mol%. The as prepared glasses are transparent and have an amorphous network structure. On the ... 详细信息

Glasses in the system 24.5Na2O·24.5CaO·6P2O5·xSrO·(45-x)SiO2 have been studied in the composition region of x = 0 - 15 mol%. The as prepared glasses are transparent and have an amorphous network structure. On the otherhand, heat treated glasses are transformed to opaque white glass ceramic characterized by their highly crystalline network structure. Crystalline apatite (calcium phosphate, Ca3(PO4)2, wollastonite (calcium silicate, CaSiO3), and strontium calcium phosphate Ca2Sr(PO4)2 are the main well-formed cry

关键词： Structure Physical Properties Gasses Glass Ceramics

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电渣重熔过程的建模及智能控制方法

控制与决策 2010年第3期25卷 425-429页

作者：曹方王伟大连理工大学电子与信息工程学院辽宁大连116023

针对电渣炉系统是一个多变量耦合、时滞、参数时变的复杂被控对象,系统难以控制的缺陷,通过大量实验和分析,确立了熔速、磁性调压与二次电压、熔炼电流的相互关系,建立起工程化的控制模型,并提出一种智能控制方法,包括多变量解耦控制策... 详细信息

针对电渣炉系统是一个多变量耦合、时滞、参数时变的复杂被控对象,系统难以控制的缺陷,通过大量实验和分析,确立了熔速、磁性调压与二次电压、熔炼电流的相互关系,建立起工程化的控制模型,并提出一种智能控制方法,包括多变量解耦控制策略、滞后时间模糊自整定和粒子群优化算法整定PID控制器参数.工业应用表明,该方法克服了电渣炉的非线性和强耦合,控制精度高,具有较强的鲁棒性和适应性.

关键词：电渣重熔解耦 PID控制器粒子群优化算法

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Adaptive Agent-Based Modeling Framework for Collective Decision-Making in Crowd Building Evacuation

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Journal of Shanghai Jiaotong university(Science) 2021年第4期26卷 522-533页

作者： CHEN Feier ZHA0 Qiyuan ca0 Mingming CHEN Jiagi FU Guiguan State Key Laboratory of Ocean Engineering Key Laboratory of Marine Intelligent Equipment and System of Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China Marautec Co. Ltd.Shanghai201206China Zhiyuan College Shanghai Jiao Tong UniversityShanghai200240China School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai200240China Institute of Fintech Shanghai University of Finance and EconomicsShanghai200433China

Crowd evacuation in different situations is an important topic in the research field of safety. This paper presents a hybrid model for heterogeneous pedestrian evacuation simulation. Our adaptive agent-based model (ABM) combines the strength of human crowd behavior description from classical social force models with discrete dynamics expression from cellular automaton models by extending the conception of floor field. Several important factors which may influence the results of decision-making of pedestrians are taken into consideration, such as the location of sign, the attraction of exit, and the interaction among pedestrians. To compare the effect of information on the pedestrians, we construct three decision-making mechanisms with different assumptions. To validate these three simulation models, we compare the numerical results from different perspectives with rational range in the case study where the Tampere Theater evacuation was carried out. The ABM framework is open for rules modification and could be applied to different building plans and has implication for architectural design of gates and signs in order to increase the evacuation efficiency.

关键词： adaptive agent-based model evacuation simulation emergency interaction heterogeneity

Upscaling conductivity and porosity in three-dimensional heterogeneous porous media

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Chinese Science Bulletin 2004年第22期49卷 2415-2423页

作者： ZHANG Yong Hydrologic Science,University of california,Davis,ca 95616,USA Desert Research Institute,2215 Raggio Parkway,Reno,NV 89512,USA Hydrologic Science University of California Davis CA 95616 United States Desert Research Institute 2215 Raggio Parkway Reno NV 89512 United States

An empirical formula is presented to upscale the conductivity of 3-dimensional heterogeneous porous me- dia, in which the distribution of local-scale conductivity is non-Gaussian with a high variance. The upscaled conductiv- ity is determined as a function of the volumetric proportion, the spatial connectivity and the statistical geometric length of high-permeable inclusions, and the arithmetic mean of con- ductivities of all hydrofacies. A systematic comparison to other traditional upscaling methods indicates that this em- pirical formula provides a better estimation of the equivalent conductivity. In the second part of this study, numerical ex- periments of solute migration reveal that porosity also needs to be upscaled to capture the transport of contaminants in a heterogeneous medium using an effective or upscaled homo- geneous medium. This is due to the tendency of contaminants to be preferrentially transported by 3-dimensional pathways composed of high-permeable materials in heterogeneous aquifer systems. The apparent difference between the actual transport velocity of contaminants and the upscaled velocity, based on the equivalent conductivity, forces upscaling of po- rosity. Further systematic analyses demonstrate that the up- scaled porosity follows a non-linear trend as the content of high-permeable sediments decreases. Resultant upscaled porosity, with values varying between 0.004 and 1.5, is be- yond the definition of the traditional porosity on the representative elementary volume (REV) scale. When the content of high-permeable materials is less than 30%, the upscaling of porosity is critical in the simulation of the contaminant transport in a heterogeneous medium using an upscaled, homogeneous counterpart.

关键词：标度方法传导率多孔性三维空间异类多孔介质多孔材料

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Potential detoxification of aflatoxin B2 using Kluyveromyces lactis and Saccharomyces cerevisiae integrated nanofibers

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BIOCelL 2017年第2期41卷 67-73页

作者： MAHMOUD MOUSTAFA TAREK TAHA MOHAMED elNOUBY NEHAL el-DEEB GAMAL HAMAD M.A.ABUSAIED SULAIMAN ALRUMMAN Department of Biology College of ScienceKing Khalid University9004AbhaKingdom of Saudi Arabia(KSA) Botany Department Faculty of ScienceSouth Valley UniversityQenaEgypt Environmental Biotechnology Department Genetic Engineering and Biotechnology Research Institute(GEBRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Composite and Nanostructured Materials Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Department of Biopharmaceutical Product Research Genetic Engineering and Biotechnology Research Institute(GEBRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Food Technology Department Arid Land Cultivation Research Institute(ALCRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Polymer Materials Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt

Current investigation has shown that human exposure to aflatoxins is not limited to the administration of contaminated cereals,but water is another possible *** study was aimed to design easily applicable method to eliminate aflatoxin B2(AFB2)from contaminated drinking *** has been used for preparation of probiotic-coated polyvinyl alcohol(PVA)and cellulose acetate(ca)*** of these hybrid nanofibers were studied by scanning electron microscopy(SEM)and Fourier-transformed infrared spectroscopy(FT-IR).SEM showed the proper coating of probiotic strains(Kluyveromyces lactis CBS 2359 and Saccharomyces cerevisiae ATCC 9763)on both nanofiber *** areas(1-5 cm^(2))of the probiotic-nanofiber hybrid were used to enhance the removal of 20 ng/ml of aflatoxin B2(AFB2)from prepared AFB2-contaminated water over *** revealed that a 5 cm^(2) area of probiotic-coated PVA nanofibers can eliminate 97.5% of AFB2 as compared to 87.5%,90.5%,93.5%,and 95.5%,for 1 cm2,2 cm^(2),3 cm^(2),and 4 cm^(2),respectively,while probiotic-coated ca nanofibers were slightly less ***,the cytotoxicity of probiotics-ca treated water on cultured human fibroblasts was almost 10 times lower than the cytotoxicity recorded in probiotics-PVA treated ***,results of the current research suggest that probiotics-polymer nanofiber membranes can be used as an extra stage in the water purification system for the treatment of AFB2-contaminated water.

关键词： Nanofibers Aflatoxin B2 Cytotoxicity Water treatment

Perspectives on atmospheric mercury and its fate in aquatic ecosystems

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Journal of Environmental Sciences 2000年第S1期12卷 85-91页

作者： D.B. Porcella (1034 Lindsey Court, Lafayette ca 94549 USA E mail: dporcell@***)

Mercury (Hg) is a neurotoxin to humans and wildlife that has a quantitatively important gas phase that makes its atmospheric cycle an important part of exposure pathways to these organisms. The important atmospheric forms are elemental Hg (Hg(0)), inorganic gas phase Hg (HgH gs ), and inorganic particulate Hg(HgIIp). Each form has different behavior depending on its chemical and physical properties. Generally, scientists have found with trace metal clean sampling and analytical techniques, that background Hg levels are 1—2 ng/m\+3 in air, 0.1—2 ng/L in surface waters, 5—25 ng/L in rainwater, and less than 0.1 μg/g in sediments remote from natural Hg minerals and wastewater sources. Values in excess of these concentrations generally indicate local anthropogenic influences or contaminated samples. Broad scale estimates of Hg inputs to the atmosphere suggest that annual anthropogenic fluxes to the atmosphere as Hg(0) are about 40 percent of the total global cycle, oceanic evasion is about 40 percent, and (by difference) the remaining input to the global cycle (20 percent) is evasion from terrestrial sources, largely via soils and vegetation. This paper summarizes recent data that will constrain estimates from these sources. For example, terrestrial sources could approach 40 percent and annual anthropogenic inputs be correspondingly less. Furthermore, a historic perspective is needed because Hg has cycled atmospherically over geologic time. In addition to the uncertainty in source quantification, methylation must be a focus of risk analysis, because this process is responsible for risks to human and ecosystem health for almost all modern day Hg exposures.

关键词： Perspectives on atmospheric mercury and its fate in aquatic ecosystems

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AN INSTABILITY THEORY OF AIR-SEA INTERACTION FOR COASTAL UPWelLING

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Advances in Atmospheric Sciences 1988年第3期5卷 277-285页

作者： P.C. Chu Department of Oceanography Naval Postgraduate School, Monterey, ca 93943, U.S.A. Department of Oceanography Naval Postgraduate School Monterey USA

A surface wind (seabreeze), thermally generated by differential sea surface temperature, is introduced to Gill-Clarke’s model (1974) through wind stress for investigating the effects of seabreeze on coastal upwel-ling. A coupled air-sea system is treated as an eigenvalue problem. The solutions show that the thermally forced local winds break down the coastal Kelvin wave into three parts: small-scale (Lcale (100 kmcaying and fast-moving modes, and ’large’-scale (L>200 km) coastal Kelvin modes. The consistency of the length scale between the most growing mode predicted by this model and the observed cold/warm alternation pattern of surface water near the Peruvian Coast (around 15 °S) implies that seabreeze may play some role in coastal upwelling.

关键词： mode AN INSTABILITY THEORY OF AIR-SEA INTERACTION FOR COASTAL UPWelLING length SEA

Moving toward an understanding of the metastatic process in hepatocellular carcinoma

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World Journal of Gastroenterology 2001年第6期7卷 777-778页

作者： W.Michael Korn Division of Gastroenterology and Comprehensive cancer canter,University of california San Francisco,San Francisco,ca 94143-0128,USA Division of Gastroenterology and Comprehensive cancer Center University of California San Francisco 94143-0128 USA. mkorn@cc.ucsf.edu

INTRODUCTIONClinical factors contributing to the therapeutic challenge of hepatocellular carcinoma (HCC) are manifold :tumors arise often in patients with compromised liver function ,therefore limiting therapeutic options ;symptoms develop only at later stages of tumor progression ,and tumors tend to invade normal stuctures or occur in multiple locations simultaneously.

关键词： Animals carcinoma, Hepatocellular Humans Liver Neoplasms Neoplasm Metastasis

Vegetation Analysis and Soil Characteristics on Two Species of Genus AchilleaGrowing in Egyptian Desert

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Open Journal of Ecology 2015年第9期5卷 420-433页

作者： Yasser Ahmed el-Amier el-Sayed Fouad el-Halawany Samia Ali Haroun Sura Goma Mohamud Department of Botany Faculty of Science Mansoura University Mansoura Egypt

The present study provides a vegetation analysis and species distribution at 50 sites, emphasizing the environmental factors that affect species distribution. A total of 74 plant species belonging to 67 genera and related to 23 families of vascular plants are recorded. Asteraceae, Poaceae, Chenopodiaceae, Brassicaceae, Fabaceae and Zygophyllaceae are the largest families, and therophytes (41.89) and chamaephytes (24.32%) are the most frequent, indicating a typical desert life-form spectrum. Chorological analysis revealed that 25 of the studied species were Mediterranean taxa, Saharo-Sindian chorotypes, either pure or penetrated into other regions, comprised 47 species. After application of the TWINSPAN and Dca programs, 4 vegetation groups (A-D) were identified, groups A and B were dominated by Achillea santolina, group C was codominated by Zygophyllm coccinum and Launaea spinosa and group D was dominated by Leptadenia pyrotechnica. Groups A and B may represent the vegetation types of the Western Mediterranean coast of Egypt, while groups C and D may represent the Wadi Hagul. The linear correlation of soil variables with the importance values of some dominant species and the application of canonical Correspondence Analysis (Cca-biplot) indicates significant associations between the floristic composition of the studied area and the edaphic factors such as electrical conductivity, pH, calcium carbonate, sulphates, bicarbonate, cations (Na+, K+, ca++ and Mg++) and PAR.

关键词： Achillea Soil Analysis Western Mediterranean Coast Wadi Hagul Chorotype

Tetrandrine inhibits ca2+-activated chloride channel in cultured human umbilical vein endothelial cells

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Acta Pharmacologica Sinica 2004年第3期25卷 73-79页

作者： Qi-zhi FANG1,2,Ning ZHONG1,3,Yi ZHANG1,Zhao-nian ZHOU1,4 1Physiological Lab of Hypoxia,Shanghai Institute of BiologicalSciences,Chinese Academy ofSciences,Shanghai200031,China 3Department of Molecular and Cell Biology,University of california at Berkeley,Berkeley,ca 94720,USA 2 Now in cardiovascularResearch Institute,University of cali- fornia at San Francisco,San Francisco,ca 94143,USA Physiological Laboratory of Hypoxia Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 上海 200031

AIM: To characterize the electrophysiological and kinetic properties of ca2+-activated chloride channel (caCC) in cultured human umbilical vein endothelial cell line (HUVEC), and test the inhibitory effects of tetrandrine (Tet) on caCC. METHODS: ca2+-activated Cl- currents (ICl,ca) were recorded by patch-clamp whole cell configurations. [ca2+]i was measured via intracellular Fura-2 fluorescence intensities. RESULTS: ICl,ca was activated by increasing [ca2+]i via direct elevation of intracellular calcium. ICl,ca showed an apparent outward rectification properties, and it was activated in a voltage- and calcium-dependent mode. Tet dose-dependently inhibited ICl,ca, the IC50 was (5.2±0.4) μmol/L (n=8 cells). Tet suppressed both voltage-dependent and calcium-dependent activation of ICl,ca. The activa- tion time constant was (326±12) ms [in the presence of 10 μmol/L Tet, compared to control (175±17) ms, at +100 mV], and ca2+ concentration for half maximal activation was (387±61) nmol/L for Tet (compared to control (287±36) nmol/L. CONCLUSIONS: Tet effectively blocked ICl,ca, and such effects might be due to its inhibitory effects on the activation process of ca2+-activated chloride channel.

关键词： chloride channels endothelium tetrandrine patch-clamp techniques calcium