检索结果-南通市图书馆

Chinese Physics B 2018年第3期27卷 444-450页

作者： F trabelsi H Dhaouadi o Riahi t othman Universite de tunis El-Manar Faculte des Sciences de TunisLaboratoire de physique de la matiere molle et de modelisation electromagnetique(LP3ME)Campus Universitaire Farhat Hached 2092 Tunis Tunisie

In this work we perform a theoretical calculation in order to reconstitute the （E-t） phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα＊ transition. this reconstruction is carried out on the basis of a thermo-dynamic calculation of the slope of the curve joining the SmC＊ domain and the unwound SmC＊. An empiric correction of the mean field term of Landau De-Gennes development is necessary to accomplish this reconstruction. thereafter, an experimental validation is performed to verify our calculations.

关键词： field-temperature phase diagram liquid orystal

Vibrational resonance in a multistable system with position-dependent mass

在线全文

学校读者我要写书评

暂无评论

Communications in theoretical Physics 2023年第11期75卷 115-134页

作者： t o Roy-Layinde K A omoteso o t Kolebaje F o ogunmefun R A Fasasi J A Laoye U E Vincent Department of Physics Olabisi Onabanjo UniversityAgo-IwoyeOgun StateNigeria Department of Physics Adeyemi Federal University of EducationOndoNigeria Department of Physical Sciences Redeemer’s UniversityP.M.B.230EdeNigeria Department of Physics Lancaster UniversityLancaster LA14 YBUnited Kingdom

the occurrence of vibrational resonance(VR)in a dual-frequency-driven multistable system with a spatially varying mass modelling particle with position-dependent mass(PDM)and evolving in a one-dimensional symmetric periodic potential has been investigated and reported in this *** numerically compute and analyze the response amplitude,the effects of the PDM parameters(m0,a)on the potential structure,the occurrence of VR and the bifurcation of the equilibrium *** is shown that the PDM parameters,besides controlling VR,can induce unconventional resonance patterns through the variation of the potential well *** resonant states can be influenced through the cooperation of the PDM parameters and the external forcing leading the system from multiresonance state into single and double resonance *** contributions of the fixed rest mass m0 on the VR and the PDM-induced resonance are determined by threshold conditions imposed by the magnitude of the mass nonlinear strength a.

关键词： vibrations resonance position-dependent mass multistable oscillator dualfrequency force nonlinear systems

Emissions from the combustion of eucalypt and pine chips in a fluidized bed reactor

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2016年第4期28卷 246-258页

作者： E.D.Vicente L.A.C.tarelho E.R.teixeira M.Duarte t.Nunes C.Colombi V.Gianelle G.o.da rocha A.Sanchez de la Campa C.A.Alves Centre for Environmental and Marine Studies Department of Environment and PlanningUniversity of Aveiro Regional Centre for Air Quality Monitoring Environmental Monitoring Sector ARPA Federal University of Bahia Chemical Institute40170-290Campus de Ondina Centre for Research in Sustainable Chemistry (CIQSo) Joint Research Unit to CSIC "Atmospheric Pollution"University of HuelvaCampus El Carmen

Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution,reduced costs and improved efficiency of *** the European Union（EU）energy directive,biomass is a suitable renewable *** aim of this study was to experimentally quantify and characterize the emission of particulate matter（PM（2.5））resulting from the combustion of two biomass fuels（chipped residual biomass from pine and eucalypt）,in a pilot-scale bubbling fluidized bed（BFB）combustor under distinct operating *** variables evaluated were the stoichiometry and,in the case of eucalypt,the leaching of the *** Co and PM（2.5）emission factors were lower when the stoichiometry used in the experiments was higher（0.33±0.1 g Co/kg and 16.8±1.0 mg PM（2.5）/kg,dry gases）.the treatment of the fuel by leaching before its combustion has shown to promote higher PM（2.5）emissions（55.2±2.5 mg/kg,as burned）.organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass,while carbonate（Co3^（2-））accounted for between 2.3 and 8.5 wt.%.the particulate mass was mainly composed of inorganic matter（71% to 86% of the PM（2.5）mass）.Compared to residential stoves,BFB combustion generated very high mass fractions of inorganic *** was the water soluble ion in higher concentration in the PM（2.5）emitted by the combustion of eucalypt,while calcium was the dominant water soluble ion in the case of pine.

关键词： Biomass Combustion Fluidized bed PM2.5emissions Chemical composition

F4-tCNQ concentration dependence of the current voltage characteristics in the Au/P3Ht:PCBM:F4-tCNQ/n-Si(MPS) Schottky barrier diode

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2014年第11期23卷 512-522页

作者： E.Yaglioglu o.tzn ozmen Department of Physics Faculty of Arts and Sciences Dzce University

In this study, we investigate some main electrical parameters of the gold/poly（3-hexylthiophene）：[6,6]-phenyl C61 bu- tyric acid methyl ester：2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane/n-type silicon （Au/P3Ht：PCBM：F4-tCNQ/n- Si） metal-polymer-semiconductor （MPS） Schottky barrier diode （SBD） in terms of the effects of F4-tCNQ concentration （0%, 1%, and 2%）. F4-tCNQ-doped P3Ht：PCBM is fabricated to figure out the p-type doping effect on the device per- formance. the main electrical parameters, such as ideality factor （n）, barrier height （ФB0）, series resistance （Rs）, shunt resistance （Rsh）, and density of interface states （Nss） are determined from the forward and reverse bias current-voltage （l-V） characteristics in the dark and at room temperature. the values of n, Rs, ФB0, and Nss are significantly reduced by using the 1% F4-tCNQ doping in P3Ht：PCBM：F4-tCNQ organic blend layer, additionally, the carrier mobility and current are increased by the soft （1%） doping. the most ideal values of electrical parameters are obtained for 1% F4-tCNQ used diode. on the other hand, the carrier mobility and current for the hard doping （2%） become far away from the ideal diode values due to the unbalanced generation of holes/electrons and doping-induced disproportion when compared with 1% F4-tCNQ doping. these results show that the electrical properties of MPS SBDs strongly depend on the F4-tCNQ doping and doping concentration of interfacial P3Ht：PCBM：F4-tCNQ organic layer. Moreover, the soft F4-tCNQ dop- ing concentration （1%） in P3Ht：PCBM：F4-tCNQ organic layer significantly improves the electrical characteristics of the Au/P3Ht：PCBM：F4-tCNQ/n-Si （MPS） SBDs which enables the fabricating of high-quality electronic and optoelectronic devices.

关键词： P3Ht:PCBM:F4-tCNQ interfacial organic layer F4-tCNQ doping concentration Schottky bar-rier diodes I-V characteristics

Agro-residue biochar and N fertilizer addition mitigates Co2-C emission and stabilized soil organic carbon pools in a rain-fed agricultural cropland

在线全文

学校读者我要写书评

暂无评论

International Soil and Water Conservation Research 2021年第1期9卷 76-86页

作者： Segun o.oladele Adewole t.Adetunji Department of Agronomy Adekunle Ajasin University Akungba AkokoOndo StateNigeria Department of Crop Soil and Pest ManagementFederal University of Technology AkureOndo StateNigeria Department of Agriculture Cape Peninsula University of TechnologyWestern CapeSouth Africa

Scarce carbon dioxide(Co_(2))emission data,soil organic carbon(C_(org))and labile C_(org) pool index for croplands in sub-Saharan Africa(SSA)limits our ability to define regional Co_(2) flux and mitigation prospects provided by biochar ***,we conducted a two-year field scale study quanti-fying effects of biochar(12t ha^(-1)),biochar(12t ha^(-1))and N fertilizer(90 kg N ha^(-1)),N fertilizer(90 kg N ha^(-1))alone and control(no amendment)on C_(org),C_(org) pools,lability index(LI)and Co_(2) emissions of a humid tropical alfisol under rainfed rice *** clearly demonstrate that biochar amendment combined with N fertilizer significantly increased C_(org),particulate organic carbon,and particulate organic carbon to organic carbon ***,this combination decreased dissolved organic carbon,dissolved organic carbon to organic carbon proportion,easily oxidizable carbon,easily oxidizable carbon to organic carbon proportion,microbial biomass carbon,microbial biomass carbon to organic carbon proportion,LI,and Co_(2) emission when compared to other *** findings established relationship between labile C_(org) pools and Co_(2) ***,our study suggest that application of biochar and N fertilizer addition can decrease Co_(2) emission from SSA croplands under rainfed rice cultivation,increase essential labile C_(org) pools,protect labile C_(org) pools sensitive to losses and sequester C_(org) with positive implication for global change mitigation and soil quality improvement.

关键词： Global change Sub-saharan Africa Greenhouse gas Rainfed croplands Environment

Effects of tiC addition on properties of laser particle deposited WC-Co-Cr and WC-Ni coatings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

transactions of Nonferrous Metals Society of China 2013年第12期23卷 3634-3642页

作者： B.A.oBADELE P.A.oLUBAMBI o.t.JoHNSoN Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology

the mechanisms by which titanium carbide （tiC） improves the properties of tungsten carbide （WC） coatings deposited on duplex stainless steels using laser particle injection technique were investigated. the relationships between laser process parameters and the synthesized composite were studied. the morphologies and microstructures of the feedstock powders and composite coatings were characterized using scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDX） techniques. Surface hardness of the composite layers was determined using the Vickers microhardness tester while its corrosion behaviour in 3.5%NaCl solution was investigated by potentiodynamic polarization curve measurement method. As a result of the laser treatment, microstructures characterized by hard ceramic particles with strong bonding to substrate were formed on the surface layer of the steels. the addition of tiC to WC resulted in microstructures free from cracks, pores and intermetallics which could be detrimental to the properties of the composites. High microhardness was observed and most of the coatings shifted the corrosion potential to more noble values with the pseudo-passive curve.

关键词： laser particle injection titanium carbide tungsten carbide corrosion behaviour hardness

Efficiency of Legumes in Increasing Yam Yield under Sandy Ferrasol in the Forest Zone of Southwestern Côte d’Ivoire

在线全文

学校读者我要写书评

暂无评论

open Journal of Soil Science 2024年第4期14卷 227-236页

作者： Germaine A. tanoh Félix B. o. Bouadou Jean Baptiste D. Ettien Department of Soil Sciences Water and Geomaterials University of Felix Houphou&#235t Boigny Abidjan C&#244te d&#8217Ivoire Department of Food Security and Nutrition Swiss Center for Scientific Research in C&#244te d&#8217Ivoire Abidjan C&#244te d&#8217Ivoire

the cropping system is based on traditional farming in rural areas. In this way, yields of some food crops like yam are very low considering their high need for nutrients. the nutrient-rich land is under high land pressure as it is occupied by cash crops such as oil palm and rubber at the expense of food crops and soil fertility is declining. the study was conducted in Grand-Lahou to assess the effect of organic matter provided by legumes in increasing yam yield. the randomized complete block design included four (4) treatments: Arachis hypogaea + yam association (t1), Acacia mangium + yam association (t2), Arachis + Acacia mangium + yam association (t3) and pure yam crop (t0). the parameters measured were: the soil nutrients content, the rate of mineralization of organic matter through the C/N ratio as well as the yield of yam through different techniques that allowed the objective of the study to be achieved. It was noted a slight improvement of nitrogen and organic carbon in all treatments with a higher value recorded in the t2 treatment. the C/N ratio decreased to 12 in all treatments compared to the control, which reflects a normal decomposition of the organic matter. treatment t1 increased yam yield (8.4 t/ha) in contrast to treatments t2 (4.1 t/ha) and t3 (2.8 t/ha). Legume-based treatments t2 and t3 were associated with a significant decrease in yam yield, resulting in losses of −46.34% to −25.09%, while treatment t1 resulted in a gain of 28.57%. As a result, the treatments involving legumes contributed to normalizing the organic matter content of the soil. the simultaneous association of these two legumes led to a decrease in yam production, contrary to the treatment associating only groundnut.

关键词： Legumes organic Matter Yam Yield Côte d’Ivoire

生长阻滞特异性转录因子5剪接变异体GAS5_o1增强慢性髓系白血病细胞对伊马替尼的敏感性

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国生物化学与分子生物学报 2024年第3期40卷 348-361页

作者：张斯玮 Gwyn t.Williams 西安医学院基础医学部生物化学与分子生物学教研室西安710021 西安医学院西安市病原微生物与肿瘤免疫重点实验室西安710021 School of Life Sciences Keele UniversityStaffordshireUK

在多种肿瘤中,生长阻滞特异性转录因子5(growth-arrest specific transcript 5,GAS5)高表达与患者的良好生存期相关。GAS5存在多种剪接变异体,本研究探讨GAS5部分剪接变异体在髓系白血病细胞系中的表达模式。并基于对凋亡诱导敏感的慢... 详细信息

在多种肿瘤中,生长阻滞特异性转录因子5(growth-arrest specific transcript 5,GAS5)高表达与患者的良好生存期相关。GAS5存在多种剪接变异体,本研究探讨GAS5部分剪接变异体在髓系白血病细胞系中的表达模式。并基于对凋亡诱导敏感的慢性髓系白血病(chronic myeloid leukemia,CML)细胞系K562,研究GAS5部分剪接变异体对K562细胞自身增殖、凋亡以及对靶向药物伊马替尼(imatinib,IM)的敏感性的影响。反转录PCR结果显示,GAS5剪接模式在髓系白血病细胞系HL-60、K562、NB4和KASUMI-1之间未见明显差异。相较于指数增长期,GAS5_AE表达水平在细胞密度引起的生长停滞期有一定程度的累积。通过核转染,将GAS5剪接变异体(pcDNA3-GAS5_1B、-GAS5_2B、-GAS5_3A、-GAS5_4A、-GAS5_o1或-GAS5_AE)转入K562细胞的单克隆株中。通过台盼蓝染色、吖啶橙染色后进行细胞计数,克隆形成实验检测细胞集落形成能力。结果与对照组相比,瞬时转染GAS5剪接变异体并无抑制细胞的基础增殖或增强细胞对药物的敏感性。建立GAS5_o1的稳定转染株,延长培养时程并计算倍增时间,发现GAS5_o1的表达水平和倍增时间成正比(R^(2)=0.5692)。在稳转株o1-C8中观察到GAS5_o1可促进IM引起的细胞生长抑制(56.94%±2.84%vs.36.07%±2.32%,Po1的上调可能增加CML细胞的倍增时间,并使CML细胞对IM处理敏感。

关键词：生长阻滞特异性转录因子5 剪接变异体慢性髓系白血病凋亡

Functional lumen imaging probe use in a high-volume practice:Practical and technical implications

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Endoscopy 2024年第7期16卷 396-405页

作者： Yan Jiang Raul Vazquez-Reyes Afrin Kamal thomas Zikos George triadafilopoulos John o Clarke Division of Gastroenterology and Hepatology Stanford University School of MedicineRedwoodCA 94063United States

BACKGRoUND the functional lumen imaging probe(FLIP)is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal ***,widespread adoption of FLIP remains limited and its utility in highvolume practices remains *** to analyze large sample data on clinical use of FLIP and provide insight on several technical aspects when performing *** We conducted a retrospective comparative and descriptive analysis of FLIP procedures performed by a single provider at an academic medical *** was a total of 398 FLIP procedures *** medical records were reviewed and data regarding demographics and procedural details were *** tests,including chi-squared,t-test,and multivariable logistic and linear regression,were *** there was an increase in FLIP cases with each successive time period of 13 months(n=68,146,184,respectively)with notable rises specifically for indications of dysphagia and gastroesophageal reflux *** was a shift toward use of the longer FLIP balloon catheter for diagnostic purposes(overall 70.4%vs 29.6%,Pormed in conjunction with other diagnostics/interventions,such as dilation and wireless pH probe *** were nearly equally performed with anesthesia vs moderate sedation(51.4%anesthesia),with no major *** who had anesthesia were less likely to have recurrent antegrade contractions[odds ratio(oR)=0.4,95%CI:0.3-0.8]and were also more likely to have absent contractility(oR=2.4,95%CI:1.3-CoNCLUSIoN FLIP cases have increased in our practice with expanding indications for its *** limited normative data,providers should be aware of several potential technical issues,including the possible impact of sedation choice when assessing esophageal motility patterns.

关键词： Gastroenterology Endoscopy Functional lumen imaging probe Esophagus Motility

Simple and High-Yield Synthesis of a thinner Layer of Graphenic Carbon from Coconut Shells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2024年第5期12卷 969-979页

作者： Retno Asih Haniffudin Nurdiansah Mochamad Zainuri Deni S.Khaerudini Angelinus t.Setiawan A.Y.Dias Pudji Untoro Ahmad Sholihand Darminto Department of Physics Institut Teknologi Sepuluh NopemberSurabaya60111Indonesia Department of Material and Metallurgical Engineering Institut Teknologi Sepuluh NopemberSurabaya60111Indonesia Research Centre for Advanced Materials National Research and Innovation Agency(BRIN)Tangerang Selatan15314Indonesia Pt.Graphene Nanomaterial Consulting Malang65141Indonesia Department of Physical Engineering Surya UniversityBanten15143Indonesia

Biomass has become of recent interest as a raw material for‘green’graphenic carbon(GC)since it promotes an environmentally friendly ***,we investigate a single pyrolysis route to synthesize GC from coconut shells which provides a simple method and can produce a high yield,thus being convenient for large-scale *** pyrolysis involves a stepped holding process at 350℃ for 1 h and at 650℃ or 900℃ for 3 *** GC sample resulted at the 900℃ pyrolysis has a thinner sheet,a less porous structure,a higher C/o ratio,and an enhanced electrical conductivity than those pyrolyzed at 650℃.the addition of Na3Po4 catalyst has no signiﬁ-cant effects on the GC structures obtained by this *** single pyrolysis route generates thinner GC sheets compared to the two-step heat treatment followed by the liquid phase exfoliation(LPE)***,the latter method offers a formation of clean samples with a porous or holey feature which has potential for advanced energy-storage applications.

关键词： Graphenic carbon biomass coconut shells pyrolysis synthesis route