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HEMTs）；栅槽；数字湿法腐蚀；选择性湿法腐蚀 1

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主动式队列管理；传输控制协议；往返时滞；史密斯预估器 1

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Selective pseudosolubilization capability of

Fei HUA, Hongqi WANG

《环境科学与工程前沿（英文）》 2013年第7卷第4期页码 539-551 doi: 10.1007/s11783-013-0498-z

摘要： Pseudosolubilized ability of sp. DG17 on -alkanes, role of biosurfactants in -octadecane uptake and trans-membrane transport mechanism of -octadecane were studied by analyzing amount of pseudosolubilized oil components in water phase, and the fraction of radiolabeled C -octadecane in the broth and cell pellet. GC-MS results showed that pseudosolubilized oil components were mainly C to C of -alkanes. In -octadecane broth, pseudosolubilized -octadecane could be accumulated as long as pseudosolubilized rate was faster than mineralization rate of substrate, and the maximum concentration of pseudosolubilized -octadecane achieved to 45.37 mg·L . All of these results showed that sp. DG17 mainly utilized alkanes by directly contacting with pseudosolubilized small oil droplets in the water phase. Analysis of C amount in cell pellet revealed that an energy-dependent system mainly controlled the trans-membrane transport of -octadecane.

关键词： Pseudomonas alkane uptake pseudosolubilization trans-membrane transport

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Transport and selectivity of indium through polymer inclusion membrane in hydrochloric acid medium

Xiaorong Meng, Conghui Wang, Pan Zhou, Xiaoqiang Xin, Lei Wang

《环境科学与工程前沿（英文）》 2017年第11卷第6期 doi: 10.1007/s11783-017-0950-6

摘要： In the present paper, a polymer inclusion membrane (PIM) containing polyvinyl chloride (PVC), and bis-(2-ethylhexyl) phosphate (D2EHPA) which was used as extracting agent was used for the recovery of In(III) ions in hydrochloric acid medium. The effects of carrier concentration, feed phase pH, strip phase HCl concentration, temperature on the transport, and the membrane’s stability and thickness were examined. And the conditions for the selective separation of In(III) and Cu(II) were optimized. The results showed that the transport of In(III) across PIM was consistent with the first order kinetics equation, and also it was controlled by both the diffusion of the metal complex in the membrane and the chemical reaction at the interface of the boundary layers. The transport flux ( ) was inversely proportional to the membrane thickness, however, the transport stability improved as the membrane thickness increased. The transport flux of In(III) and Cu(II) was decreased by excessive acidity of feed phase and high concentration of Cl . The selectivity separation coefficient of In(III)/Cu(II) was up to 34.33 when the original concentration of both In(III) and Cu(II) was 80 mg·L as well as the pH of the feed phase and the concentration of Cl in the adjusting context were0.6 and 0.5 mol·L , respectively. Within the range of pH= 1–3, the separation selectivity of In(III)/Cu(II) reached the peak in the case when the Cl concentration was 0.7 mol·L .

关键词： Polymer inclusion membrane Selective transport D2EHPA In(III) Cu(II)

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变环境压力下的激光选区熔化——介观尺度模型与输运现象 Article

胡仁志, 罗曼乐兰, 黄安国, 吴甲民, 魏青松, 文世峰, 张李超, 史玉升, Dmitry Trushnikov, V. Ya. Belenkiy, I. Yu. Letyagin, K.P. Karunakaran, 庞盛永

《工程（英文）》 2021年第7卷第8期页码 1157-1164 doi: 10.1016/j.eng.2021.07.003

摘要：

近期研究表明，相比常压条件下，采用真空或低压环境的激光选区熔化（SLM）工艺可获得缺陷更少、表面质量更优的打印件。虽然通过高速摄像实验已经对SLM工艺在真空环境下的介观物理过程进行了部分研究，但该工艺下影响熔池传热和流动方面的深层机理仍不十分清楚。为此，基于最近的激光焊接模型工作，我们首次建立了变环境压力下SLM工艺的介观尺度数学模型。我们模拟了大气压和100 Pa低压环境下SLM工艺中316L粉末的输运现象。研究发现，在典型工艺参数（激光功率：200 W；扫描速度：2 ms^-1；粉末直径：27 µm）下，大气环境中熔池表面凹坑的平均温度将近2800 K，而在100 Pa环境压力时，平均温度仅为2300 K。由于在100 Pa低压条件下，蒸发引起的表面压力和环境压力之间的压差相对于大气环境下的压差更大，更易驱动高温流体流动，因此熔池表面流动速度更加剧烈（平均速度约为4 m·s^-1）。研究表明，熔池表面周期性的波浪流动（周期：14 µs）直接影响堆积体的表面粗糙度。此外，由于雷诺数小于400且远低于湍流临界值，熔融金属液流动模式为层流，因此，黏性耗散的影响至关重要。在真空或低环境压力条件下，波纹的流动轨迹更长，使得波动更容易由于黏性效应被耗散，从而改善了打印件的表面粗造度。总之，我们的数学模型阐明了变环境压力下SLM工艺实验研究中观察到的有趣输运现象的物理机制，它有望成为优化SLM工艺过程的有力工具。

关键词：激光选区熔化介观尺度模型环境压力输运现象

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The source and transport of bioaerosols in the air: A review

《环境科学与工程前沿（英文）》 2021年第15卷第3期 doi: 10.1007/s11783-020-1336-8

摘要：

• Emission of microbe from local environments is a main source of bioaerosols.

关键词： Bioaerosols Diffusion Source identification Biogeography

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Intercontinental transport of air pollution

Lin ZHANG,

《环境科学与工程前沿（英文）》 2010年第4卷第1期页码 20-29 doi: 10.1007/s11783-010-0014-7

摘要： There is an increasing interest on the intercontinental transport of air pollution among the three main emission regions at northern mid-latitudes: North America, Europe, and East Asia. Air pollutants with sufficient long lifetime can be transported from one continent to another. Observations from ground sites, aircraft and satellites have demonstrated this intercontinental-scale transport of air pollutants in the free troposphere. Numerical models have been applied to understand the pathways of the transport and the impact of intercontinental pollution transport. This paper reviews current observational evidence and modeling studies of intercontinental transport of ozone and its precursors, and the resulting impacts on air quality.

关键词： intercontinental transport ozone air pollution

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Future urban transport management

《工程管理前沿（英文）》页码 534-539 doi: 10.1007/s42524-023-0255-3

摘要： The incorporation of disruptive innovations into the transportation industry will inevitably cause major upheavals in the transportation sector. However, existing research lacks systematic theories and methodologies to represent the underlying characteristics of future urban transport systems. Furthermore, emerging modes in urban mobility have not been sufficiently studied. The National Natural Science Foundation of China (NSFC) officially approved the Basic Science Center project titled “Future Urban Transport Management” in 2022. The project members include leading scientists and engineers from Beijing Jiaotong University, Beihang University, and Beijing Transport Institute. Based on a wide range of previous projects by the consortium on urban mobility and sustainable cities, this project will encompass transdisciplinary and interdisciplinary research to explore critical issues affecting future urban traffic management. It aims to develop fundamental theories and methods based on social and technological developments in the near future and explores innovative solutions to implement alongside these emerging developments in urban mobility.

关键词： future urban transport management travel behavior characteristics transportation operations transportation emergency management transportation decision intelligence

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Thermal transport properties of monolayer phosphorene: a mini-review of theoretical studies

Guangzhao QIN, Ming HU

《能源前沿（英文）》 2018年第12卷第1期页码 87-96 doi: 10.1007/s11708-018-0513-y

摘要： Phosphorene, a two-dimensional (2D) elemental semiconductor with a high carrier mobility and intrinsic direct band gap, possesses fascinating chemical and physical properties distinctively different from other 2D materials. Its rapidly growing applications in nano-/opto-electronics and thermoelectrics call for fundamental understanding of the thermal transport properties. Considering the fact that there have been so many studies on the thermal transport in phosphorene, it is on emerging demand to have a review on the progress of previous studies and give an outlook on future work. In this mini-review, the unique thermal transport properties of phosphorene induced by the hinge-like structure are examined. There exists a huge deviation in the reported thermal conductivity of phosphorene in literature. Besides, the mechanism underlying the deviation is discussed by reviewing the effect of different functionals and cutoff distance in calculating the thermal transport properties of phosphorene. It is found that the (vdW) interactions play a key role in the formation of resonant bonding, which leads to long-ranged interactions. Taking into account of the vdW interactions and including the long-ranged interactions caused by the resonant bonding with large cutoff distance are important for getting the accurate and converged thermal conductivity of phosphorene. Moreover, a fundamental insight into the thermal transport is provided based on the review of resonant bonding in phosphorene. This mini-review summarizes the progress of the thermal transport in phosphorene and gives an outlook on future horizons, which would benefit the design of phosphorene based nano-electronics.

关键词： thermal transport phosphorene resonant bonding

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EFFECTS OF TRANSPORT STRESS ON THE INTESTINES INVOLVING NEURONAL NITRIC OXIDE SYNTHASE

《农业科学与工程前沿（英文）》页码 285-295 doi: 10.15302/J-FASE-2022469

摘要：

● Transport stress declined the level of leukocytes including lymphocytes in rat serum.

关键词： intestine nNOS nNOS-positive neurons transport stress

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Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

《化学科学与工程前沿（英文）》 2015年第9卷第2期页码 142-153 doi: 10.1007/s11705-015-1516-4

摘要： Recent advances with Pd containing catalysts for the selective hydrogenation of acetylene are described. The overview classifies enhancement of catalytic properties for monometallic and bimetallic Pd catalysts. Activity/selectivity of Pd catalysts can be modified by controlling particle shape/morphology or immobilisation on a support which interacts strongly with Pd particles. In both cases enhanced ethylene selectivity is generally associated with modifying ethylene adsorption strength and/or changes to hydride formation. Inorganic and organic selectivity modifiers (i.e., species adsorbed onto Pd particle surface) have also been shown to enhance ethylene selectivity. Inorganic modifiers such as TiO change Pd ensemble size and modify ethylene adsorption strength whereas organic modifiers such as diphenylsulfide are thought to create a surface template effect which favours acetylene adsorption with respect to ethylene. A number of metals and synthetic approaches have been explored to prepare Pd bimetallic catalysts. Examples where enhanced selectivity is observed are generally associated with decreased Pd ensemble size and/or hindering of the ease with which an unselective hydride phase is formed for Pd. A final class of bimetallic catalysts are discussed where Pd is not thought to be the primary reaction site but merely acts as a site where hydrogen dissociation and spillover occurs onto a second metal (Cu or Au) where the reaction takes place more selectively.

关键词： acetylene ethylene selective hydrogenation palladium bimetallic

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Preparation of polysulfone-based block copolymer ultrafiltration membranes by selective swelling and

《化学科学与工程前沿（英文）》 2022年第16卷第5期页码 745-754 doi: 10.1007/s11705-021-2038-x

摘要： Selective swelling of block copolymers of polysulfone-b-poly(ethylene glycol) is an emerging strategy to prepare new types of polysulfone ultrafiltration membranes. Herein, we prepared nanoporous polysulfone-b-poly(ethylene glycol) ultrafiltration membranes by selective swelling and further promoted their porosity and ultrafiltration performances by using CaCO₃ nanoparticles as the sacrificial nanofillers. Different contents of CaCO₃ nanoparticles were doped into the solution of polysulfone-b-poly(ethylene glycol), and thus obtained suspensions were used to prepare both self-supported and bi-layered composite structures. Selective swelling was performed on the obtained block copolymer structures in the solvent pair of ethanol/acetone, producing nanoporous membranes with poly(ethylene glycol) lined along pore walls. The CaCO₃ nanoparticles dispersed in polysulfone-b-poly(ethylene glycol) were subsequently etched away by hydrochloric acid and the spaces initially occupied by CaCO₃ provided extra pores to the block copolymer layers. The porosity of the membranes was increased with increasing CaCO₃ content up to 41%, but further increase in the CaCO₃ content led to partial collapse of the membrane. The sacrificial CaCO₃ particles provided extra pores and enhanced the connectivity between adjacent pores. Consequently, the membranes prepared under optimized conditions exhibited up to 80% increase in water permeance with slight decrease in rejection compared to neat membranes without the use of sacrificial CaCO₃ particles.

关键词： block copolymers selective swelling ultrafiltration CaCO₃ nanoparticles sacrificial nanofillers

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Highly efficient and selective removal of vanadium from tungstate solutions by microbubble floating-extraction

《化学科学与工程前沿（英文）》 2023年第17卷第5期页码 581-593 doi: 10.1007/s11705-022-2235-2

摘要： Selective separation of dissolved tungsten and vanadium is of great significance for the utilization of the secondary resources of these elements. In this work, selective removal of vanadium from tungstate solutions via microbubble floating-extraction was systematically investigated. The results indicated that vanadium can be more easily mineralized over tungsten from tungstate solutions using methyl trioctyl ammonium chloride as mineralization reagent under weak alkaline conditions. Owing to the higher bubble and interface mass transfer rates, high-efficiency enrichment and deep separation of vanadium could be achieved easily. Additionally, the deep recovery of tungsten and vanadium from the floated organic phase could be easily realized using a mixed solution of sodium hydroxide and sodium chloride as stripping agents. The separation mechanism mainly included the formation of hydrophobic complexes, their attachment on the surface of rising bubbles, and their mass transfer at the oil–water interface. Under the optimal conditions, the removal efficiency of vanadium reached 98.5% with tungsten loss below 8% after two-stage microbubble floating-extraction. Therefore, the microbubble floating-extraction could be an efficient approach for separating selectively vanadium from tungstate solutions, exhibiting outstanding advantages of high separation efficiency and low consumption of organic solvents.

关键词： tungsten vanadium selective separation reagent mineralization microbubble floating-extraction

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Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

《环境科学与工程前沿（英文）》 2023年第17卷第8期 doi: 10.1007/s11783-023-1701-5

摘要：

● TiO₂/ZSM-11 was prepared by a facile solid state dispersion method.

关键词： Selective dye degradation Photocatalysis TiO₂ ZSM-11 Chemisorption

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Cooling strategies and transport theories for brain hypothermia resuscitation

LIU Jing

《能源前沿（英文）》 2007年第1卷第1期页码 32-57 doi: 10.1007/s11708-007-0004-z

摘要： The brain is one of the most important organs in a biological body whose normal function depends heavily on an uninterrupted delivery of oxygen. Unlike skeletal muscles that can survive for hours without oxygen, neuron cells in the brain are easily subjected to an irreversible damage within minutes from the onset of oxygen deficiency. With the interruption of cardiopulmonary circulation in many cardiac surgical procedures or accidental events leading to cerebral circulation arrest, an imbalance between energy production and consumption will occur which causes a rapid depletion of oxygen due to the interrupted blood-flow to the brain. Meanwhile, the cooling function of the blood flow on the hot tissue will be stopped, while metabolic heat generation in the tissues still keeps running for awhile. Under such adverse situations, the potential for cerebral protection through hypothermia has been intensively investigated in clinics by lowering brain temperature to restrain the cerebral oxygen demands. The reason can be attributed to the decreased metabolic requirements of the cold brain tissues, which allows a longer duration for the brain to endure reduced oxygen delivery. It is now clear that hypothermia would serve as the principal way for neurologic protection in a wide variety of emergency medicines, especially in cerebral damage, anoxia, circulatory arrest, respiratory occlusion, etc. However, although brain cooling has been found uniquely significant in clinical practices, the serious lack of knowledge on the mechanisms involved prevents its further advancement in brain resuscitation. Compared with the expanded trials in clinics, only very limited efforts were made to probe the engineering issues involved, which turns out to be a major obstacle for the successful operation of brain hypothermia resuscitation. From the viewpoint of biothermal medical engineering, the major theories and strategies for administering brain cooling can generally be classified into three categories: heat transfer, oxygen transport and cooling strategy. Aiming to provide a complete overview of the brain hypothermia resuscitation, this article comprehensively summarizes the recent progresses made in theoretical, practical and experimental techniques in the area. Particularly, attention is paid to the mathematical models to quantify the heat and oxygen transport inside the cerebral tissues. Typical cooling strategies to effectively lower brain temperature and thus decrease oxygen consumption rate in the cerebral tissues are analyzed. Approaches to deliver oxygen directly to the target tissues are discussed. Meanwhile, some future efforts worth pursuing within the area of brain cooling are suggested.

关键词： mathematical interruption hypothermia metabolic generation

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Seasonal variations of transport pathways andpotential sources of PM

Yuan Chen, Shaodong Xie, Bin Luo

《环境科学与工程前沿（英文）》 2018年第12卷第1期 doi: 10.1007/s11783-018-1009-z

摘要： Seasonal pattern of transport pathways and potential sourcesof PM in Chengdu during 2012–2013were investigated based on hourly PM data,backward trajectories, clustering analysis, potential source contributionfunction (PSCF), and concentration-weighted trajectory (CWT) method.The annual hourly mean PM concentrationin Chengdu was 97.4 mg·m . 5, 5, 5 and 3 mean clusters were generatedin four seasons, respectively. Short-distance air masses, which travelledwithin the Sichuan Basin with no specific source direction and relativelyhigh PM loadings (>80 mg·m ) appearedas important pathways in all seasons. These short pathways indicatedthat emissions from both local and surrounding regions of Chengducontributed significantly to PM pollution.The cities in southern Chengdu were major potential sources with PSCF>0.6and CWT>90 mg·m . The northeastern pathway prevailed throughoutthe year with higher frequency in autumn and winter and lower frequencyin spring and summer. In spring, long-range transport from southernXinjiang was a representative dust invasion path to Chengdu, and theCWT values along the path were 30-60 mg·m . Long-range transportwas also observed in autumn from southeastern Xinjiang along a northwesterlypathway, and in winter from the Tibetan Plateau along a westerly pathway.In summer, the potential source regions of Chengdu were smaller thanthose in other seasons, and no long-range transport pathway was observed.Results of PSCF and CWT indicated that regions in Qinghai and Tibetcontributed to PM pollution in Chengdu aswell, and their CWT values increased to above 30 mg·m in winter.

关键词： Transport pathway Backwardtrajectory Clustering analysis Potential source Chengdu