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Journal of Thermal Science 2020年第3期29卷 667-675页

作者： mAhAJAN Govinda ChO heejin smith Aaron ThOmPSON scott m. Rheem manufacturing MontgomeryAL 36109USA Department of mechanical engineering Mississippi State UniversityMsissippi StateMS 39762USA Department of mechanical engineering Auburn UniversityAubumnAL 36849USA

Oscillating heat pipes(OhP)which are constructed from a serpentine-arranged capillary tube possess a desirable aerodynamic form factor and provide for relatively high heat transfer rates via cyclic evaporation and condensation of an encapsulated working fluid with no internal wicking structure *** last two decades,OhP has been extensively investigated for its potential application in thermal management of various *** study presents an experimental investigation on the heat transfer performance of an atypically long finned *** heat transfer performance of the proposed OhP was analyzed and compared with a bare tube OhP with similar overall *** show that a unit row of finned OhP filled with n-pentane with fill ratio of 70%can recover up to(400±40)w of heat from a typical waste exhaust air *** additional pressure drop due to fins was estimated to be(6.8±2)Pa resulting in an increase of 1–2 w of fan power *** average heat recovery rate via finned OhP was found to be almost 80%more than bare tube OhP filled with same working fluid with same fill ratio.

关键词： oscillating heat pipe waste heat recovery ventilation

硫酸溶液中1,1′-硫代羰基二咪唑在碳钢上的吸附及缓蚀影响和碘离子的增强效应(英文)

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物理化学学报 2008年第7期24卷 1185-1191页

作者： SOLmAZ R meRT m. e KARDA■ G YAZICI b eRbL m Department of Chemistry Science & Letters Faculty Cukurova University Balcali Adana 01330 Turkey

The inhibition effect of 1,1′-thiocarbonyldiimidazole (TCDI) on the corrosion behaviors of mild steel (mS) in 0.5 mol·L-1 h2SO4 solution was studied with the help of potentiodynamic polarization, electrochemical impedance spectroscopy (eIS), and linear polarization resistance (LPR) techniques. The effect of immersion time on the inhibition effect of TCDI was also investigated over 72 h. For the long-term tests, hydrogen evolution with immersion time (Vh2-t) was measured in addition to the three techniques already mentioned. The thermodynamic parameters, such as adsorption equilibrium constant (Kads) and adsorption free energy (△Gads) values, were calculated and discussed. To clarify inhibition mechanism, the synergistic effect of iodide ion was also investigated. The potential of zero charge (PZC) of the mS was studied by electrochemical impedance spectroscopy method, and a mechanism of adsorption process was proposed. It was demonstrated that inhibition efficiency increased with the increase in TCDI concentration and synergistically increased in the presence of KI. The inhibition efficiency was discussed in terms of adsorption of inhibitor molecules on the metal surface and protective film formation.

关键词：腐蚀行为软钢防腐技术碘化物

Impurity effects on electrical conductivity of doped bilayer graphene in the presence of a bias voltage

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Chinese Physics b 2016年第7期25卷 316-323页

作者： e Lotfi h Rezania b Arghavaninia m Yarmohammadi Department of Physics Sanandaj Branch Islamic Azad University Department of Physics Razi University Department of Physics Kermanshah Branch Islamic Azad University Young researchers and elite Club Kermanshah Branch Islamic Azad University

we address the electrical conductivity of bilayer graphene as a function of temperature, impurity concentration, and scattering strength in the presence of a finite bias voltage at finite doping, beginning with a description of the tight-binding model using the linear response theory and Green＇s function approach. Our results show a linear behavior at high doping for the case of high bias voltage. The effects of electron doping on the electrical conductivity have been studied via changing the electronic chemical potential. we also discuss and analyze how the bias voltage affects the temperature behavior of the electrical conductivity. Finally, we study the behavior of the electrical conductivity as a function of the impurity concentration and scattering strength for different bias voltages and chemical potentials respectively. The electrical conductivity is found to be monotonically decreasing with impurity scattering strength due to the increased scattering among electrons at higher impurity scattering strength.

关键词： bilayer graphene Green's function electrical conductivity

Laser-system model for enhanced operational performance and flexibility on OmeGA eP

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high Power Laser Science and engineering 2020年第1期8卷 52-66页

作者： m.J.Guardalben m.barczys b.e.Kruschwitz m.Spilatro L.J.waxer e.m.hill Laboratory for Laser energetics University of RochesterRochesterNY 14623-1299USA

The development of laser performance models having real-time prediction capability for the OmeGA eP laser system has been essential in meeting requests from its user community for increasingly complex pulse shapes that span a wide range of energies. The laser operations model PSOPS provides rapid and accurate predictions of OmeGA eP lasersystem performance in both forward and backward directions, a user-friendly interface and rapid optimization capability between shots. we describe the model’s features and show how PSOPS has allowed real-time optimization of the lasersystem configuration in order to satisfy the demands of rapidly evolving experimental campaign needs. we also discuss several enhancements to laser-system performance accuracy and flexibility enabled by PSOPS.

关键词： laser operations high-energy laser systems pulse shaping high-energy-density physics laser-system modeling

PmmA-doped CdSe quantum dots as saturable absorber in a Q-switched all-fiber laser

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Chinese Optics Letters 2016年第8期14卷 67-71页

作者： m.b.hisyam m.F.Rusdi A.A.Latiff S.w.harun Department of electrical engineering Faculty of Engineering University of Malaya Photonics Research Center University of Malaya

we demonstrate the generation of Q-switched pulses from an ytterbium-doped fiber laser（YDFL） using quantum dot（QD） CdSe as a passive saturable absorber（SA）. The CdSe QD is fabricated by the synthesis of CdO,Se, and manganese acetate and paraffin oil and oleic acid as the solvent and surfactant, respectively. The CdSe QD is then doped into poly-methyl-methacrylate（PmmA） via an emulsion polymerization process. A PmmAhosted CdSe QD thin flake with a homogeneous end surface is then formed and placed between two ferrules and assembled in a YDFL cavity to achieve the Q-switching operation with a repetition rate of 24.45 to 40.50 khz while varying the pump power from 975 to 1196 mw. The pulse width changes from 6.78 to 3.65 μs with a maximum calculated pulse energy at 0.77 μJ at a pump power of 1101 mw. This work may be the first demonstration of CdSe QD-based Q-switching in an all-fiber configuration that should give proportional insight into semiconductor QD materials in photonics applications.

关键词： switched CdSe absorber repetition methacrylate photonics polymerization surfactant oleic demonstration

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益生素在养猪生产中是否有效

国外畜牧学（猪与禽） 2011年第2期31卷 33-36页

作者：朱勇文 m.Kenny h.Smidt e.mengheri b.miller Division of Food Animal Sciences Department of Clinical Veterinary Sciences University of Bristol Lower Langford North Somerset BS40 5DU UK Laboratory of microbiology Wageningen University Dreijenplein 10 6703 HB Wageningen The Netherlands INRAN Via Ardeatina 546 Roma 00178 Italy

在食品中加入某些活的微生物早已被证明对人类健康有积极的影响,这一方法已拓展到食品动物生产领域,且已涉及到许多微生物菌种,特别是乳酸菌、芽孢杆菌和酿酒酵母菌。对益生素兴趣的增加基本上是由于微生物耐药性问题的出现,同时自禁止... 详细信息

在食品中加入某些活的微生物早已被证明对人类健康有积极的影响,这一方法已拓展到食品动物生产领域,且已涉及到许多微生物菌种,特别是乳酸菌、芽孢杆菌和酿酒酵母菌。对益生素兴趣的增加基本上是由于微生物耐药性问题的出现,同时自禁止在动物生产中使用抗生素后,益生素被认为是一种可减少病原菌感染并可提高猪、尤其是断奶期间仔猪的健康。然而,仍有必要阐明益生素在猪生产中的作用及潜在作用机制。在评价益生菌功效时,必须考虑所用的特定菌株和治疗猪对应的生长阶段。在实际的养猪生产中,重复益生素的功效还存在问题,因为维持其活性对它们的有益功效极为关键,但利用常规的饲料加工技术难以实现。益生素微生物能够被有效投喂的一种情况是在利用液体发酵饲料的生产系统中。液体饲料可以用活的野生乳酸菌进行发酵,也可将特定分离株作为"启动子"刺激其发酵,后一种方法对发酵的可重复性及其速度有益处。养猪场的微生物应用条件对其发挥正常功效很可能是至关重要的。给利用非理想条件饲养的猪饲喂益生素,所增加的经济效益远大于采用最佳福利条件和管理措施饲养的猪。如果猪出生时使其肠道内建立一个有益的微生物菌群,就有可能会产生较为健康的猪。实现这一效果的最有效方法是给母猪服用益生素,这提供了一个扩大益生菌的手段,使新生仔猪的生活环境中到处都是值得拥有的有益菌株。相比之下,它也许足以在仔猪断奶前后向其提供一个有支持作用和保护作用的肠道菌群,因为就某些肠道菌群的不稳定和损失来说,此时期是一个重要的决定性时刻。

关键词：猪益生菌生产性能健康

维普期刊数据库博看期刊

electrooxidation of methanol and ethanol on carbon electrodeposited Ni–mgO nanocomposite

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Chinese Journal of Catalysis 2016年第4期37卷 616-627页

作者： h. b. hassana Z. Abdel hamid Rabab m. el-Sherif 开罗大学理学院化学系埃及吉萨冲央冶金研究开发研究所埃及开罗

Ni–mgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel watts bath in the presence of fine mgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of methanol and ethanol in alkaline medium was investigated and compared with that of carbon coated pure Ni （Ni/C）. The chemical composition, phase structure, and surface morphology of the deposited nano‐composites were studied by energy dispersive X‐ray spectros‐copy, X‐ray diffractometry, and scanning electron microscopy, respectively. Different electrochemi‐cal techniques were used to estimate the catalytic activity of the prepared electrocatalyst anodes, including cyclic voltammetry （CV）, chronoamperometry, and electrochemical impedance spectros‐copy （eIS）. The Ni/C electrocatalyst alone exhibited remarkably low catalytic activity and poor stability toward the electrooxidation process. The inclusion of mgO significantly promoted the cata‐lytic activity of the Ni catalyst for the alcohol electrooxidation and enhanced its poisoning re‐sistance. The eIS results confirmed those of CV and revealed a lower charge transfer resistance and enhanced roughness for the Ni–mgO/C nano‐composite electrodes compared with those of Ni/C.

关键词： Nickel-modified manganese oxide electrooxidation methanol ethanol electrochemical impedance spectroscopy Cyclic voltammetry

Improving wood volume predictions in dry tropical forest in the semi-arid brazil

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Journal of Arid Land 2020年第6期12卷 1046-1055页

作者： Robson b de LImA Patrícia A b bARReTO-GARCIA Alessandro de PAULA Jhuly e S PeReIRA Flávia F de CARVALhO Silvio h m GOmeS Department of Forest engineering State University of AmapáMacapá68900070Brazil Department of Forest Science State University of Southwest BahiaVitória da Conquista 45083900Brazil Universidade Federal de Lavras Lavras 37200900Brazil Universidade de São Paulo Piracicaba 13418900Brazil

The volumetric variability of dry tropical forests in brazil and the scarcity of studies on the subject show the need for the development of techniques that make it possible to obtain adequate and accurate wood volume *** this study,we analyzed a database of thinning trees from a forest management plan in the Contendas de SincoráNational Forest,southwestern bahia State,*** data set included a total of 300 trees with a trunk diameter ranging from 5 to 52 ***,validation and statistical selection of four volumetric models were *** to the difference in height values for the same diameter and the low correlation between both variables,we do not suggest models which only use the diameter at breast height(Dbh)variable as a predictor because they accommodate the largest estimation *** comparing the best single entry model(hohenald-Krenn)with the Spurr model(best fit model),it is noted that the exclusion of height as a predictor causes the values of 136.44 and 0.93 for Akaike information criterion(AIC)and adjusted determination coefficient(R2 adj),which are poorer than the second best model(Schumacher-hall).Regarding the minimum sample size,errors in estimation(root mean square error(RmSe)and bias)of the best model decrease as the sample size increases,especially when a larger number of trees with Dbh≥15.0 cm are randomly *** sampling by diameter class produces smaller volume prediction errors than random sampling,especially when considering all *** summary,the Spurr and Schumacher-hall models perform *** models suggest that the total variance explained in the estimates is not less than 95%,producing reliable forecasts of the total volume with *** estimates indicate that the bias around the average is not greater than 7%.Our results support the decision to use regression methods to build models and estimate their parameters,seeking stratification strategies in diameter classes for the sample trees.

关键词： volume modeling minimal sample size Caatinga Spurr model forest management

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肉鸡加工过程中环境与产品质量控制

中国家禽 2011年第6期33卷 38-40页

作者： e.Abboah-Afari b.h.Kiepper h.S.Plumber b.h.Kiepper m.e.berrang D.P.smith R.J.meinersmann T.J.Clark J.hughes b.Dean 美国乔治亚大学美国农业部美国北卡罗莱纳州立大学美国阿肯色州立大学

1采用膜过滤净化肉鸡加工废水本研究的目的旨在评价采用膜过滤对改善肉鸡加工废水水质的效果。将一定量商业肉鸡加工废水分别用1500~3000μm和508μm过滤网进行初级过滤,去除固体残渣。取4L经过初级处理的废水样品,用500/106μm过滤器... 详细信息

1采用膜过滤净化肉鸡加工废水本研究的目的旨在评价采用膜过滤对改善肉鸡加工废水水质的效果。将一定量商业肉鸡加工废水分别用1500~3000μm和508μm过滤网进行初级过滤,去除固体残渣。取4L经过初级处理的废水样品,用500/106μm过滤器进行预处理.

关键词：肉鸡加工克氏肉鸡屠宰弯曲杆菌试验鸡萘啶酸酮酸聚砜膜挥发性固体总悬浮固体量屠体胴体 COD 化学需氧量水质污染固体物聚偏二氟乙烯膜鼠伤寒沙门菌日龄

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刺松藻多糖抗肿瘤及免疫调节作用研究

刺松藻多糖抗肿瘤及免疫调节作用研究

作者：吴荣杰辽宁师范大学

学位级别：硕士

刺松藻多糖（CFPS）具有重要的生物活性。研究表明其具有免疫调节的作用：可增强T淋巴细胞、b淋巴细胞、巨噬细胞（mφ）、淋巴因子激活杀伤细胞（lymphokine activated killer cells, LAK）、自然杀伤细胞（natural killer cell, NK　c... 详细信息

刺松藻多糖（CFPS）具有重要的生物活性。研究表明其具有免疫调节的作用：可增强T淋巴细胞、b淋巴细胞、巨噬细胞（mφ）、淋巴因子激活杀伤细胞（lymphokine activated killer cells, LAK）、自然杀伤细胞（natural killer cell, NK　cell）,以及白细胞介素-2（interleukin2,IL-2）等免疫相关因子的作用。目前在临床抗肿瘤方面,主要用于联合放化疗、辅助药物治疗和改善预后等方面。本文分别采用热水浸提-乙醇沉淀法从刺松藻中提取分离刺松藻多糖（CFPS）,mTT法检测CFPS对人肺腺癌细胞A549细胞体外生长的影响,对正常C57bL/6J小鼠脾淋巴细胞增殖、脾淋巴细胞和mφ抑瘤活性的影响;中性红比色法检测CFPS对C57bL/6J鼠脾巨噬细胞mφ吞噬活性影响;采用细胞划痕实验和boyden chamber迁移模型研究CFPS对A549细胞迁移的影响;通过免疫细胞化学方法和RT-PCR的方法检测CFPS对于A549细胞凋亡相关基因bcl-2水平的影响;以Lewis肺癌C57bL/6J小鼠为模型,检测CFPS对肿瘤生长、脾脏和胸腺的影响;采用eLISA法检测荷瘤小鼠的细胞免疫指标;使用免疫组化和流式细胞技术对小鼠肺癌组织进行凋亡检测,探讨CFPS抗肿瘤和免疫调节作用机制。结果表明,CFPS1000μg/ml时对体外培养的A549细胞生长有抑制作用,能有效抑制细胞迁移,同时能很好的降低bcl-2在转录和翻译水平的细胞中含量,500μg/ml CFPS能显著增强淋巴细胞增殖和mφ吞噬活性（p＜0.05）,提高其抑瘤效果;体内实验结果显示,低浓度、高浓度CFPS组抑瘤率分别为39%、42%,与对照组相比,差异有统计学意义（p＜0.05）,荷瘤小鼠的免疫分子IL-1、IL-2、IL-6、IL-10、IL-12、IL-18、IFN-γ、 FAS-L血清分泌水平,与对照组相比,都有显著提高（p＜0.05）;CFPS组肿瘤组织免疫组化和流式细胞技术结果都显示出明显有凋亡发生。 CFPS在体外对A549有一定的抑制作用,可以提高免疫细胞的分子免疫应答水平;在体内可改善Lewis肺癌C57bL/6J鼠的免疫指标,通过激活机体免疫系统实现有效的抗肺癌活性和免疫调节作用。

关键词：刺松藻多糖抗肿瘤免疫调节