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A STUDY ON THE FLUX, SPECIATION, AND BUDGET OFMERCURY IN CONTROLLED EXPEEIMENTAL ECOSYSTEMS

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Journal of Oceanology and Limnology 1987年第2期 146-160页

作者：陆贤崑,吴晋平,k.w.johnson,F.A.whitney,C.S.wong Shandong College of Oceanology Third Institute of Oceanography SOA Institute of Ocean Sciences Sidney B.C. Canada Institute of Ocean Sciences Sidney B.C. Canada Institute of Ocean Sciences Sidney B.C. Canada

The lowest addition of mercury (0.1 ug Hg 1-1) was used in CEEs for research on mercury flux, speciation and budget. The removal behavior of mercury by phytoplankton in water columns of CEEs can be described by first order kinetic equations for total and particulate mercury in the CEE spiked by mercury. The removal rate of mercury in water columns depends on the size and productivity of phytoplanton in a water column to which mercuric ions were added. A 4.4 day half-life time and a 2.8 day half-life time for total and particulate mercury respectively was obtained in diatom bloom. During microflagellate bloom a 30 day total mercury half-life time was estimated with increase of particulate mercury in the water column. The 0.010 ug Hg cm-2y-1 mercury flux rate that was attained in the control bag agreed with the values from field measurements in Saanich Inlet where the bags were *** proportion of total mercury to dissolved and particulate mercury depended also on the size, productivity, and concen

关键词： In SPECIATION A STUDY ON THE FLUX AND BUDGET OFMERCURY IN CONTROLLED EXPEEIMENTAL ECOSYSTEMS

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海水中ng/Ⅰ级汞的贮存及行为研究

分析化学 1986年第2期 98-101+89页

作者：陆贤崑 k.w.johnson C.S.wong 山东海洋学院化学系 Institute of Ocean Sciences B.C.Sidhey Canada Institute of Ocean Sciences B.C.Sidhey Canada

关于天然水含汞样品的贮存问题,已经研究了十年以上。多数作者认为,贮存天然水样的主要问题来自汞在容器壁上的吸附,造成样品汞损失严重。汞的挥发损失被认为是第二个重要误差来源。但对上述两种损失的比例,不同作者的结果相差较远。另... 详细信息

关于天然水含汞样品的贮存问题,已经研究了十年以上。多数作者认为,贮存天然水样的主要问题来自汞在容器壁上的吸附,造成样品汞损失严重。汞的挥发损失被认为是第二个重要误差来源。但对上述两种损失的比例,不同作者的结果相差较远。另外,容器内汞的溶出沾污也被认为是贮存时的可能误差来源。保存天然水样品的方法可归为选择适当保护剂及适当容器。保护剂可分为:酸(硝酸、硫酸等),氧化剂(高锰酸钾、过硫酸钾、四氯代金酸等),以及络合配位体(氯离子、碘离子、氰离子等)。常用容器有Pyrex等硬质玻璃瓶、聚乙烯或聚四氟乙烯容器。不过不同作者对容器材料和保护剂类型所提出的结果有时相互矛盾。作者认为,容器预处理、样品介质、分析方法灵敏度,尤其是样品中汞浓度,都会对结果产生重大影响。目前,外海海水汞的浓度范围在0.5—8ng/L。比七十年代中期测得范围低约一个数量级。该低含量汞的海水贮存性质,尚缺具体研究。本文取加拿大沙奈奇湾(Saanich Inlet)天然海水,用不同容器和保护剂,进行贮存实验研究。

关键词：海水保护剂 ng 聚乙烯瓶无机汞聚四氟乙烯含氟高聚物

中型海洋围隔生态系中汞通量、形态和收支的研究

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海洋与湖沼 1986年第4期 307-317页

作者：陆贤崑 k.w.johnson F.A.whitney C.S.wong 吴晋平山东海洋学院海洋科学研究所海洋科学研究所海洋科学研究所国家海洋局第三海洋研究所青岛悉尼加拿大悉尼加拿大悉尼加拿大厦门

在海洋围隔生态系实验中加入迄今最低浓度的无机汞,以研究汞的迁移通量、形态分布和收支。加汞后,汞从水柱中被排除的行为可用一级反应动力学描述。在该生态系内汞被排除的半寿期,与初级生产力和浮游植物特性如个体大小、浮游能力等有... 详细信息

在海洋围隔生态系实验中加入迄今最低浓度的无机汞,以研究汞的迁移通量、形态分布和收支。加汞后,汞从水柱中被排除的行为可用一级反应动力学描述。在该生态系内汞被排除的半寿期,与初级生产力和浮游植物特性如个体大小、浮游能力等有关。对照围隔生态系内,0.01μg Hg/cm2·a的汞垂直通量与海湾现场测量值一致。在自然条件下,溶解汞是水中的主要形态,占73％。加汞后,颗粒汞迅速上升,可达70％以上。浮游植物对汞的富集因子为10～5级。汞在沉积物、器壁和水体中的回收只占52.3％。

关键词：围隔生态系总汞初级生产力生物生产力浮游植物水生植物鞭毛藻颗粒汞硅藻无机汞收支

Integrins and their potential roles in mammalian pregnancy

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Journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： Gregory A.johnson Robert C.Burghardt Fuller w.Bazer Heewon Seo Joe w.Cain Department of Veterinary Integrative Biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA Department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the sc

关键词： Humans Implantation Integrins Pigs Pregnancy Rodents Sheep

Comparison of a Spectral Bin and Two Multi-Moment Bulk Microphysics Schemes for Supercell Simulation:Investigation into key Processes Responsible for Hydrometeor Distributions and Precipitation

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Advances in Atmospheric Sciences 2024年第5期41卷 784-800页

作者： Marcus johnson Ming XUE Youngsun JUNG Center for Analysis and Prediction of Storms University of OklahomaNormanOK 73072USA School of Meteorology University of OklahomaNormanOK 73072USA Office of Science and Technology Integration National Weather ServiceSilver SpringMD 20910USA

There are more uncertainties with ice hydrometeor representations and related processes than liquid hydrometeors within microphysics parameterization(MP)schemes because of their complicated geometries and physical *** supercell simulations are produced using the wRF model coupled with“full”Hebrew University spectral bin MP(HU-SBM),and NSSL and Thompson bulk MP(BMP)***-SBM downdrafts are typically weaker than those of the NSSL and Thompson simulations,accompanied by less rain ***-SBM produces more cloud ice(plates),graupel,and hail than the BMPs,yet precipitates less at the *** limiting mass bins(and subsequently,particle size)of rimed ice in HU-SBM and slower rimed ice fall speeds lead to smaller melting-level net rimed ice fluxes than those of the *** from plates in HU-SBM,together with snow–graupel collisions,leads to a greater snow contribution to rain than those of the *** HU-SBM’s fall speeds using the formulations of the BMPs after aggregating the discrete bin values to mass mixing ratios and total number concentrations increases net rain and rimed ice ***,they are smaller in magnitude than bulk rain,NSSL hail,and Thompson graupel net fluxes near the ***,the melting-layer net rimed ice fluxes are reduced when the fall speeds for the NSSL and Thompson simulations are calculated using HU-SBM fall speed formulations after discretizing the bulk particle size distributions(PSDs)into spectral *** results highlight precipitation sensitivity to storm dynamics,fall speed,hydrometeor evolution governed by process rates,and MP PSD design.

关键词： precipitation spectral bin microphysics bulk microphysics parameterization microphysics processes wRF model supercell storm

A Dynamic Network Game of the Fintech Industry

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Journal of the Operations Research Society of China 2024年第1期12卷 5-33页

作者： David w.k.Yeung Leon A.Petrosyan Ying-Xuan Zhang SRS Consortium for Advanced Study in Cooperative Dynamic Games Shue Yan UniversityHong KongChina Center of Game Theory St Petersburg State UniversitySaint PetersburgRussia Department of Finance Asia UniversityTaichung CityTaiwanChina Faculty of Applied Mathematics-Control Processes and Center of Game Theory St Petersburg StateUniversitySaint PetersburgRussia

Economies of scale,economies of scope,and technology spillover are decisive eco-nomic elements that are crucial to the development in the Fintech *** externalities are often realized through network *** this paper,we presenta dynamic network ofﬁnancialﬁrms which exhibits these decisive *** game equilibria are characterized.A Pareto efﬁcient solution involving col-laboration of allﬁrms is *** obtain a fair-share distribution of cooperativegains,the Shapley value is adopted as the sharing *** distributionmechanisms which guarantee the fulﬁlment of the Shapley value distribution in eachstage of the cooperation duration are derived.

关键词： Network game Network equilibria Shapley value Pareto efﬁcientcooperation

Iso-propyl caprylate and iso-propyl linolenate synthetic fluids as novel alternatives in deep-water drilling operations:Critical fluid properties and aerobic biodegradability assessments

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Petroleum 2024年第2期10卷 254-264页

作者： Adewale johnson Folayan Adewale Dosunmu Aleruchi Boniface Oriji Department of Petroleum and Gas Engineering University of Port Harcourt University of Port Harcourt

Present drilling fluids for deep water wells have severe degenerative effect on the environment with high operational and disposal costs. Thus, making them less desirable in recent times. Ester synthetic drilling fluid provides a novel environmentally friendly alternative but conventional ester-based drilling fluids exhibit high viscosities in deep-water wells causing excessive equivalent circulating density(ECD) and increased risk of lost circulation owing to narrow mud density window. This study experimentally investigates the critical fluid properties and aerobic biodegradability potentials of two newly developed deep-water synthetic ester drilling fluids namely: iso-propyl caprylate(COIPE) and iso-propyl linolenate(LOIPE) synthetic fluids and their comparison with synthetic-paraffin(SP-SBF) and isomerized-olefin(IOSBF) synthetic hydrocarbon fluids. The esters of iso-propyl caprylate and iso-propyl linolenate were produced from the isolation of ester mixtures that were obtained from the homogeneous catalytic transesterification of coconut and linseed plant oil biomass respectively. The COIPE was isolated from the coconut oil iso-propyl ester mixture by low-pressure fractional distillation technique. while fractional distillation and crystallization were used to isolate the LOIPE ester from the linseed oil iso-propyl ester mixture. Meanwhile, the aerobic biodegradation investigation was conducted by a modified oxygen consumption respirometry technique. The GC-MS analysis of the COIPE and LOIPE showed that the former contains essentially of lower saturated carbon compounds(C8). whereas the latter contains higher molecular weight and unsaturated carbon compounds(C18+). The COIPE and LOIPE kinematic viscosity values are in good agreement with that of the reference synthetic hydrocarbon fluid samples(SP-SBF and IO-SBF).Although, the COIPE synthetic ester has lower viscosity value owing to the presence of shorter chain and saturated carbon atoms(C8 esters). Similarly,

关键词： Aerobic biodegradation Critical fluid properties Deep-water wells Esters' isolation: isomerized-olefin (IO-SBF) Iso-propyl caprylate (COIPE) Iso-propyl linolenate (LOIPE) Respirometry technique Synthetic-paraffin (SP-SBF)

Detecting fake reviewers in heterogeneous networks of buyers and sellers:a collaborative training-based spammer group algorithm

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Cybersecurity 2024年第2期7卷 44-67页

作者： Qi Zhang Zhixiang Liang Shujuan Ji Benyong Xing Dickson k.w.Chiu Shandong Provincial key Laboratory of wisdom Mine Information Technology Shandong University of Science and TechnologyQingdao 266590ShandongChina Zhejang University-University of linois at Urbana-Champaign Institute Haining 314499ZhejiangChina School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Faculty of Education The University of Hong KongPok Fu LamHong KongChina

It is not uncommon for malicious sellers to collude with fake reviewers(also called spammers)to write fake reviews for multiple products to either demote competitors or promote their products'reputations,forming a gray industry *** detect spammer groups in a heterogeneous network with rich semantic information from both buyers and sellers,researchers have conducted extensive research using Frequent Item Mining-based and graph-based ***,these methods cannot detect spammer groups with cross-product attacks and do not jointly consider structural and attribute features,and structure-attribute correlation,resulting in poorer detection ***-fore,we propose a collaborative training-based spammer group detection algorithm by constructing a heterogene-ous induced sub-network based on the target product set to detect cross-product attack spammer *** jointly consider all available features,we use the collaborative training method to learn the feature representations of *** addition,we use the DBSCAN clustering method to generate candidate groups,exclude innocent ones,and rank them to obtain spammer *** experimental results on real-world datasets indicate that the overall detection performance of the proposed method is better than that of the baseline methods.

关键词： Spammer group Heterogeneous network Collaborative training DBSCAN

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： k.D.küntz D.koutroumpa w.R.Dunn A.Foster F.S.Porter D.G.Sibeck B.walsh The Henry A.Rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

while we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).with a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances