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浮选模拟动力学模型的分解

国外金属矿选矿 1986年第12期 29-39页

作者： e.T.Woodburn p.j.Wallin 王婷

本文用总体物质特性描述了工业浮选中尾矿流量的摸拟原理。而总体物质特性又为每个单体物质的化学、矿相分析和离散分布所决定。离散分布可以是非连续的,抑或是连续的,这要由实实验所观察到的动力学确定。模型是根据表征空气界面和连续... 详细信息

本文用总体物质特性描述了工业浮选中尾矿流量的摸拟原理。而总体物质特性又为每个单体物质的化学、矿相分析和离散分布所决定。离散分布可以是非连续的,抑或是连续的,这要由实实验所观察到的动力学确定。模型是根据表征空气界面和连续矿浆相间总体物质固有分布特性的充气速率与平衡效应的动力学作用而建立的。该模型可以用来求解近似的一阶速率常数。充气速率用β系数摸拟.泡沫稳定性参数。和特定浮选槽的充气速率QA的乘积与α系数成比例。在不影响物质离散分类的情况下,根据浮选网络摸拟原理,便很容易确定具体的β系数了。因此,这种摸拟可以适应随充气速率和泡沫稳定性改变而改变的操作变数。显然,β系数能很好地描述一系列实验室试验的充气速率变化效应。但是;这种模型不能很好地适应那种随时间变化而泡沫稳定性降低的情况。浮选过程的动力学模型,对设计和实际操作都是很重要的。它可以为复杂的工业网络摸拟提供依据。原矿性质的变化、处理量的变化都会严重地影响网络的操作。工厂操作的变动,不易在生产前就能估计到。因此,在特定条件下,根据整套已知的参数,要求摸拟程序具有确定参数和预测工厂操作的双重功能。参数的确定,既可按在线也可按离线分批试验获得。现存模型通常以处理量改变及不变参数的假定来预测随时间变化的操作变化。此外,也可望预测操作行为的局部效应。

关键词：浮选槽废水处理设备速率常数泡沫稳定性等式物质回归参数单体一阶尾矿 β系数 QA 定义

establishment and development of the World Association for Sedimentation and erosion Research

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International journal of Sediment Research 2023年第6期38卷 901-909页

作者： Cheng Liu Zhaoyin Wang Des e.Walling International Research and Training Center on erosion and Sedimentation Department of Hydraulic engineering Tsinghua University Geography Faculty of EnvironmentScience and EconomyUniversity of Exeter

problems of soil erosion and sedimentation are issues of global *** the intensification of global change and the impacts of human activities,many countries are facing severe challenges from wideranging sediment-related *** prevention and control of sediment disasters and the rational use of soil and sediment resources are important requirements for the sustainable development strategies of all *** sediment problems are closely related to social,economic,and other human activities,the effective solution of sediment problems requires the concerted efforts of experts in different fields and thus an interdisciplinary approach is *** view of the increasing recognition of sediment as a topic of global significance and the need to promote interdisciplinary research in this field,the World Association for Sedimentation and erosion Research(WASeR) was inaugurated in *** this paper the history of the establishment of WASeR is reviewed and its main activities are briefly *** series of International Symposia on River Sedimentation(ISRS) has served as the official symposium of WASeR since *** triennial technical events have been held in China,Russia,japan,South Africa,and Germany with about 2,000 *** addition to sponsoring the ISRS,WASeR has to date also sponsored/organized or co-sponsored/co-organized over 30 other international conferences,workshops,training courses,and study tours besides sponsoring the *** adoption of the International journal of Sediment Research(IjSR) as the official journal of WASeR in 2004has also played an important role in increasing the exposure of the *** activities have served to raise WASeR’s profile as well as promoting collaboration with agencies and other organizations working in the field of erosion and *** types of prizes and honors are awarded by *** include the International Qian Ning prize for erosion and Sedimentation Technolog

关键词： erosion and sedimentation Association Symposia journal

Organic-inorganic halide perovskites for memristors

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journal of Semiconductors 2023年第9期44卷 39-46页

作者： Memoona Qammar Bosen Zou jonathan e.Halpert Department of Chemistry Hong Kong University of Science and Technology(HKUST)Clear Water Bay RoadKowloon 999077Hong Kong SARChina

Organic-inorganic halides perovskites(OHps)have drawn the attention of many researchers owing to their astonishing and unique optoelectronic *** have been extensively used for photovoltaic applications,achieving higher than 26%power conversion efficiency to *** materials have potential to be deployed for many other applications beyond photovoltaics like photodetectors,sensors,light-emitting diodes(LeDs),and *** address the looming challenge of Moore’s law and the Von neumann bottleneck,many new technologies regarding the computation of architectures and storage of information are being extensively *** the discovery of the memristor as a fourth component of the circuit,many materials are explored for memristive ***,researchers have advanced the exploration of OHps for memristive *** materials possess promising memristive properties and various kinds of halide perovskites have been used for different applications that are not only limited to data storage but expand towards artificial synapses,and neuromorphic *** we summarize the recent advancements of OHps for memristive applications,their unique electronic properties,fabrication of materials,and current progress in this field with some future perspectives and outlooks.

关键词： organic-inorganic halide perovskites resistive switching memristors

eco-Friendly phyto-Synthesis of Silver Nanoparticles Using jatropha Seedcake extract

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Chinese physics Letters 2013年第12期30卷 165-169页

作者： Anjali Bose Haresh Keharia M.p.Deshpande BRD School of Biosciences Sardar Patel MaidanVadtal RoadP.O.Box 39Satellite CampusSardar Patel UniversityVallabh Vidyanagar 388120GujaratIndia Department of physics Sardar Patel UniversityVallabh Vidyanagar 388120GujaratIndia

phytosynthesis of metal nanoparticles is gaining importance due to their biocompatibility,low toxicity and eco-friendly *** the present study,an aqueous extract of jatropha seedcake(jSC)is assessed as a reducing and stabilizing agent for the synthesis of silver nanoparticles(AgNps).The maximum reduction of silver ions occur when 1 mM AgNO_(3) solution is treated with 0.1 volume fraction of jSC extract in boiling water bath for 10 *** synthesis of AgNps is monitored by the excitation of surface plasmon resonance using UV-vis *** AgNps are found to be mono-dispersed,spherical with average particle size of 10.48±74 nm when analyzed by transmission electron *** selected area electron diffraction(SAeD)ring pattern indicated the polycrystalline nature of the *** x-ray diffraction data further confirm the presence of characteristic(111),(200),(220),(311)and(222)diffraction planes of face centered cubic structure,and the calculated lattice parameter comes out to be 4.083Å.FTIR analysis reveals the involvement of proteins and phenols in reduction and stabilization of *** synthesized AgNps have significant antibacterial action on both the Gram positive and negative bacteria.

关键词： silver synthesis stabilization

Co-inoculation of selected nodule endophytic rhizobacterial strains with Rhizobium tropici promotes plant growth and controls damping off in common bean

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pedosphere 2020年第1期30卷 98-108页

作者： Linnajara De VASCONCeLOS MARTINS FeRReIRA Fernanda De CARVALHO júlia FONSeCA COLOMBO ANDRADe Damiany páDUA OLIVeIRA Flávio Henrique VASCONCeLOS De MeDeIROS Fatima Maria De SOUZA MOReIRA Sector of Biology Microbiology and Biological ProcessesDepartment of Soil ScienceUniversidade Federal de LavrasLavras C.P.3037-37200-000(Brazil) Instituto Federal do pará/IFpA Campus MarabáRuralMarabáC.P.041-68508-979(Brazil) Universidade Federal de Lavras Department of PhytopathologyLavras C.P.3037-37200-000(Brazil)

production of common bean(phaseolus vulgaris)is limited by the occurrence of damping off(rhizoctoniosis),which is caused by the fungus Rhizoctonia ***,the co-inoculation of plant growth-promoting rhizobacteria(pGpR)involved in biological control along with diatomic nitrogen(N2)-fixing rhizobia can enhance N nutrition and increase *** this context,finding microorganisms with synergistic effects that perform these two roles is of fundamental importance to ensure adequate yield *** aim of this study was to evaluate the effects of co-inoculation of nodule endophytic strains of the genera Bacillus,paenibacillus,Burkholderia,and pseudomonas with Rhizobium tropici CIAT 899,an N2-fixing rhizobial strain,on the biocontrol of damping off and growth promotion in common bean *** experiments were conducted under axenic conditions using the common bean cultivar pé*** first experiment evaluated the potential of the 14 rhizobacterial strains,which were inoculated alone or in combination with CIAT 899,for the control of *** second experiment evaluated the ability of these 14 rhizobacterial strains to promote plant growth with three manners of N supply:co-inoculation with CIAT 899 at low mineral N supply(5.25 mg N mL^-1),low mineral N supply(5.25 mg N mL^-1),and high mineral N supply(52.5 mg N mL^-1).The use of rhizobacteria combined with rhizobia contributed in a synergistic manner to the promotion of growth and the control of damping off in the common ***-inoculation of the strains UFLA 02-281/03-18(pseudomonas sp.),UFLA 02-286(Bacillus sp.),and UFLA 04-227(Burkholderia fungorum)together with CIAT 899 effectively controlled damping *** the common bean,mineral N supply can be replaced by the co-inoculation of CIAT 899 with plant growth-promoting strains UFLA 02-281/02-286/02-290/*** endophytes UFLA02-281/02-286 are promising for co-inoculation with CIAT 899 in the common bean,promoting synergy with rhizobial i

关键词： Bacillus sp. biological control Burkholderia fungorum CIAT 899 phaseolus vulgaris plant growth-promoting rhizobacteria pseudomonas sp. Rhizoctonia solani

Data-driven evaluation of fatigue performance of additive manufactured parts using miniature specimens

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journal of Materials Science & Technology 2019年第6期35卷 1137-1146页

作者： H.Y. Wan G.F. Chen C.p. Li X.B. Qi G.p. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China School of Materials Science and engineering University of Science and Technology of China Shenyang 110016 China Materials Manufacturing Qualification Group Corporate Technology Siemens Ltd. China Beijing 100102 China State Key Laboratory of Tribology Tsinghua University Beijing J00084 China

This overview firstly introduces the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens. Some key factors for size effects sensitive to microstructures including the specimen thickness, grain size and a ratio between them are highlighted to summarize some general rules for size effects. Then, ongoing research progress and new challenges in evaluating the fatigue performance of additive manufactured parts controlled by location-specific defects, microstructure heterogeneities as well as mechanical anisotropy using miniature specimen testing technique are discussed and addressed. Finally, a potential roadmap to establish a data-driven evaluation platform based on a large number of miniature specimen-based experiment data,theoretical computations and the ’big data’ analysis with machine learning is proposed. It is expected that this overview would provide a novel strategy for the realistic evaluation and fast qualification of fatigue properties of additive manufactured parts we have been facing to.

关键词： Additive manufacturing Miniature specimen Fatigue Size effect Location-specific Data analysis

effects and mechanisms of silibinin on human hepatoma cell lines

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World journal of Gastroenterology 2007年第40期13卷 5299-5305页

作者： john j Lah Division of Gastroenterology University of CaliforniaIrvine Medical Center101 The City DriveBuilding 53Suite 113OrangeCA 92868United States

AIM： To investigate in vitro effects and mechanisms of silibinin on hepatocellular carcinoma （HCC） cell growth, MeTHODS： Human HCC cell lines were treated with different doses of silibinin. The effects of silibinin on HCC cell growth and proliferation, apoptosis, cell cycle progression, histone acetylation, and other related signal transductions were systematically examined. ReSULTS： We demonstrated that silibinin significantly reduced the growth of HUH7, HepG2, Hep3B, and pLC/pRF/5 human hepatoma cells. Silibinin-reduced HuH7 cell growth was associated with significantly up- regulated p21/CDK4 and p27/CDK4 complexes, down- regulated Rb-phosphorylation and e2F1/Dp1 complex. Silibinin promoted apoptosis of HuH7 cells that was associated with down-regulated survivin and upregulated activated caspase-3 and -9. Silibinin＇s antiangiogenic effects were indicated by down-regulated metalloproteinase-2 （MMp2） and CD34. We found that silibinin-reduced growth of HuH7 cells was associated with increased activity of phosphatase and tensin homolog deleted on chromosome ten （pTeN） and decreased p-Akt production, indicating the role of pTeN/ pI3K/Akt pathway in silibinin-mediated anti-HCC effects. We also demonstrated that silibinin increased acetylation of histone H3 and H4 （AC-H3 and AC-H4）, indicating a possible role of altered histone acetylation in silibininreduced HCC cell proliferation. CONCLUSION： Our results defined silibinin＇s in vitro anti-HCC effects and possible mechanisms, and provided a rationale to further test silibinin for HCC chemoprevention.

关键词： Hepatocellular carcinoma HuH7 cells Silibinin Chemoprevention Cell cycle Cell cycleprogression Apoptosis Acetylation of histone

Diagenetic and Reservoir Quality Variation of Miocene Sandstone Reservoir Analogues from Three Basins of Southern California,USA

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journal of earth Science 2020年第5期31卷 930-949页

作者： Sunday e.Okunuwadje David MacDonald Stephen Bowden School of Geosciences University of AberdeenAberdeen AB243UEUK Department of Geology University of BeninBenin City PMB 1154Nigeria

The Miocene sandstone deposits in the Southern California region are important hydrocarbon reservoirs. However, their development has been very challenging due to the wide variability in their reservoir quality. These sandstones have been studied from three sedimentary basins by petrographic thin section, scanning electron microscope, and X-ray diffraction to evaluate and compare the influence of diagenesis on their reservoir quality in these basins. Four petrofacies, namely p1(sand injectite or dyke), p2(sub-marine fan), p3(turbidite and marine-influenced alluvial fans) and p4(continental sandstones) have been identified. p1 and p2 characterise the sandstones in the San joaquin forearc basin and are affected by kaolinite and extensive early calcite diagenesis. p3 and p4 delineate the sandstones in the Cajon Valley and Salton Trough strike-slip basins and are dominated by smectite, mixed illite-smectite, early calcite and late calcite diagenesis. early calcite cement in p3 and p4 is in lower proportion than in p1 and p2. Although the dissolution of these sandstones by acidic fluids did not have a pattern, it, however, has the most considerable influence on p2 creating moldic pores which are expected to increase pore connectivity. The relatively abundant dissolution pores in p2, together with the absence of late authigenic calcite and illite clay in comparison to the other petrofacies studied are likely to make this sandstone facies the best reservoir targets in the Southern California region. These rocks are analogous to producing reservoirs in the region. However, because, petroleum accumulation in these reservoirs are compartmentalized by early calcite cement, maximum recovery using acidified fluids is recommended to dissolve the calcite-filled pores in order to increase connectivity of their pore network and enhance flow potential.

关键词： diagenesis petrofacies reservoir quality Miocene California

Forecast Hesitancy: Why are people Reluctant to Believe, Accept, or Respond to Various Weather, Water, and Climate Hazard-Related Forecasts?

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International journal of Disaster Risk Science 2021年第4期12卷 600-609页

作者： Michael H.Glantz Gregory e.pierce Consortium for Capacity Building(CCB) Institute for Arctic and Alpine Research(INSTAAR)University of ColoradoBoulderCO80301USA

Current discussions of the social phenomenon of“vaccine hesitancy”with regard to Covid-19 provide an opportunity to use hesitancy as a means to shift thinking about untimely and delayed responses to forecasts of hydrometeorological ***,that is,provides a paradigm through which such regrettably delayed responses to hydromet hazards might be better understood and effectively *** exaggeration,just about every hydromet event provides an example of how hesitancy hinders individual,community,and national government risk-reducing preventive and mitigative responses to forecasts of foreseeable,relatively near-term climate,water,or weather *** for such hesitancy(for vaccine and forecast use alike)include—among others—lack of trust in the science,lack of confidence in government,and persistent concern about the uncertainties that surround forecasting—both meteorological and public *** such,a better understanding of the causes that lead to individual and group hesitancy can better inform hydromet forecasters and affected communities about ways in which beneficial actions in response to timely forecasts are often *** better understanding will facilitate,where necessary,targeted interventions to enhance the societal value of forecasting by reducing this long-observed challenge of“forecast hesitancy.”First,this article focuses on incidents of“vaccine hesitancy”that,for various reasons,people around the world are even now experiencing with regard to several now-available,and confirmed efficacious,Covid-19 *** of such incidents of indecisiveness first increased dramatically over the first few months of 2021,despite the strong scientific confidence that vaccination would significantly lower personal risk of contracting as well as spreading the ***,the notion of forecast hesitancy with regard to hydrometeorological hazards is discussed.

关键词： Disaster risk reduction Forecast Forecast hesitancy Hesitancy Hydromet hazards Vaccine hesitancy