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2-基展开 1

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Susceptibility of male and female Japanese medaka (

Nannan LIU, Mei MA, Yiping XU, Jinmiao ZHA, Kaifeng RAO, Zijian WANG

《环境科学与工程前沿（英文）》 2013年第7卷第1期页码 77-84 doi: 10.1007/s11783-012-0466-z

摘要： 2,4,6-trichlorophenol (2,4,6-TCP) is a widespread probable human carcinogen and has been proven to have genotoxicity in assays. However, little genotoxicity information and no micronuclei induction data for 2,4,6-TCP is available from tests, especially for sex-specific differences. Following a preliminary test, a piscine peripheral erythrocyte micronucleus assay was conducted on medaka ( ) after a 28-day exposure to 2,4,6-TCP. In the present study, the mean micronuclei (MNC) frequencies of all of the groups increased in a dose-dependent manner, which indicated the potential genotoxicity of 2,4,6-TCP. Moreover, males were found to be more susceptible compared with females after a 28-day exposure to 2,4,6-TCP in all of the dosed groups above 10 μg·L . This is the first report on the potential of micronuclei induction and a sex-susceptible effect in the peripheral erythrocytes of mature fish after 2,4,6-TCP exposure.

关键词： 2 4 6-trichlorophenol genotoxicity Japanese medaka piscine micronucleus test in peripheral erythrocytes gender difference

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Temperature difference-powered carbon nanotube bearings

Quanwen HOU, Bingyang CAO, Zengyuan GUO

《能源前沿（英文）》 2011年第5卷第1期页码 49-52 doi: 10.1007/s11708-010-0111-0

摘要： Molecular dynamics simulations are conducted to study the motion of carbon nanotube-based nanobearings powered by temperature difference. When a temperature difference exists between stator nanotubes, the rotor nanotubes acquire a higher temperature, which arises from the interaction between phonon currents and nanotubes. The thermal driving force increases with the increase in temperature difference between the stators, an increase that is nearly proportional to the temperature difference. Confined by the minimum energy track, the (5, 5)@(10, 10) nanotube bearings only translate along the axis direction but without successive rotation.

关键词： temperature difference-induced motion carbon nanotubes nanobearing molecular dynamics simulation

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类差分平衡函数的性质及其应用

张文英,李世取

《中国工程科学》 2004年第6卷第3期页码 45-52

摘要：

定义了布尔函数的类差分和类差分平衡函数，研究了类差分平衡函数的密码学性质以及构造方法。作为类差分平衡函数的应用，给出了〓上逻辑函数是完全非线性函数的充要条件，并在首先分析得到所有四元类差分平衡函数的基础上，编程搜索出〓上所有的完全非线性函数。

关键词： Bent函数完全非线性函数 2-基展开类差分类自相关函数类差分平衡函数

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Synthesis of Intermittent-Motion Linkages with Slight Difference in Length Between Links

CHEN Xin-bo, YU Zhen

《机械工程前沿（英文）》 2006年第1卷第1期页码 76-79 doi: 10.1007/s11465-005-0007-6

摘要：

The design of intermittent-motion linkages using traditional methods is usually complicated. In this paper, (1) a new method for realizing intermittent motion, using linkages with a slight difference in length between links, is studied; (2) some new types of intermittent-motion linkages and their software for visual analysis and design are developed; and (3) influences of some design parameters on intermittent-motion characteristics are clarified. Results confirmed that the theory and the software are useful, making the synthesis of intermittent-motion linkages clear and easy.

关键词： synthesis useful intermittent intermittent-motion traditional

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温差能与低温海水资源综合利用研究

付强,王国荣,周守为,钟林,张理,余兴勇,杨浦

《中国工程科学》 2021年第23卷第6期页码 52-60 doi: 10.15302/J-SSCAE-2021.06.007

摘要：

我国海洋温差能资源量巨大，主要分布在广东省和南海海域，是区域能源结构优化以实现碳达峰、碳中和的有效支撑，也是未来我国南海、 21 世纪海上丝绸之路沿线诸多岛屿能源补给保障的重要途径；目前海洋温差能发电（ OTEC）技术和装备尚处于实验阶段，兆瓦级试验电站建设成本巨大，整体技术成熟度不及商业级利用规模，亟待发展突破。本文总结了国内外 OTEC 及综合利用的发展模式、技术装备所面临的挑战，针对南海温差能资源开发困境、广东省液化天然气（ LNG）冷能资源浪费等情况，提出了以 LNG 气化的低温海水替代深层海水进行温差能发电的新途径。建议以珠海 LNG 气化站为例，探索 LNG 冷能回收 – 温差能发电、低温冷海水综合利用示范基地的发展模式；通过初步概算示范基地的投资与收益，完成了相应模式的经济与技术可行性论证。相关发展模式建议、应用案例论证过程，可为我国温差能与低温海水资源综合利用提供技术借鉴和应用参考。

关键词：海洋温差能低温海水资源 LNG冷能综合利用温差能发电

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The Difference Effect of Environmental Regulation on Two Stages of Technology Innovation in China’s Manufacturing

Bao-long Yuan,Sheng-gang Ren,Xing Hu,Xuan-yu Yang

《工程管理前沿（英文）》 2016年第3卷第1期页码 24-29 doi: 10.15302/J-FEM-2016007

摘要： This paper divides technological innovation into two stages: technology development and technology transfer. Then the authors use the panel data of 28 manufacturing industries during 2003–2012 to test the econometric regression model for the industry of the sub stages, which is a regulation on technological innovation in the environment. The results show that: (1) environmental regulation has a significant role in promoting China’s manufacturing technology research patent achievements, and technology into new products, and this indicated that “Porter hypothesis” in the manufacturing sector has been verified; (2) R&D and transfer expenditure have a positive impact on technological innovation. Finally, the authors put forward the corresponding policy recommendations for industry of the environmental regulation on the impact of technological innovation in phases.

关键词： environmental regulation technology innovation stage difference manufacturing

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Three-dimensional finite difference analysis of shallow sprayed concrete tunnels crossing a reverse fault

Masoud RANJBARNIA, Milad ZAHERI, Daniel DIAS

《结构与土木工程前沿（英文）》 2020年第14卷第4期页码 998-1011 doi: 10.1007/s11709-020-0621-8

摘要： Urban tunnels crossing faults are always at the risk of severe damages. In this paper, the effects of a reverse and a normal fault movement on a transversely crossing shallow shotcreted tunnel are investigated by 3D finite difference analysis. After verifying the accuracy of the numerical simulation predictions with the centrifuge physical model results, a parametric study is then conducted. That is, the effects of various parameters such as the sprayed concrete thickness, the geo-mechanical properties of soil, the tunnel depth, and the fault plane dip angle are studied on the displacements of the ground surface and the tunnel structure, and on the plastic strains of the soil mass around tunnel. The results of each case of reverse and normal faulting are independently discussed and then compared with each other. It is obtained that deeper tunnels show greater displacements for both types of faulting.

关键词： urban tunnel sprayed concrete reverse fault normal fault finite difference analysis

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Molecular dynamics study of water diffusion in an amphiphilic block copolymer with large difference in

Yang Zhou, Phillip Choi

《化学科学与工程前沿（英文）》 2017年第11卷第3期页码 440-447 doi: 10.1007/s11705-017-1626-2

摘要： Isothermal-isobaric molecular dynamics simulation was used to study the diffusion mechanism of water in polyurethane- -poly( -isopropyl acrylamide) (PU- -PNIPAm) with a hydrophobic PU/hydrophilic PNIPAm mass ratio of 1.4 to 1 at 298 K and 450 K. Here, the experimental glass transition temperature ( ) of PU is 243 K while that of PNIPAm is 383 K. Different amounts of water up to 15 wt-% were added to PU- -PNIPAm. We were able to reproduce the specific volumes and glass transition temperatures (250 K and 390 K) of PU- -PNIPAm. The computed self-diffusion coefficient of water increased exponentially with increasing water concentration at both temperatures (i.e., following the free volume model of Fujita). It suggested that water diffusion in PU- -PNIPAm depends only on its fractional free volume despite the free volume inhomogeneity. It is noted that at 298 K, PU is rubbery while PNIPAm is glassy. Regardless of temperature, radial distribution functions showed that water formed clusters with sizes in the range of 0.2–0.4 nm in PU- -PNIPAm. At low water concentrations, more clusters were found in the PU domain but at high water concentrations, more in the PNIPAm domain. It is believed that water molecules diffuse as clusters rather than as individual molecules.

关键词： molecular dynamics simulation amphiphilic block copolymer free volume water diffusivity fujita model

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The inactivation of bacteriophages MS2 and PhiX174 by nanoscale zero-valent iron: Resistance difference

《环境科学与工程前沿（英文）》 2022年第16卷第8期 doi: 10.1007/s11783-022-1529-4

摘要：

• The resistance of phage PhiX174 to nZVI was much stronger than that of MS2.

关键词： Nanoscale zero-valent iron (nZVI) MS2 PhiΧ174 Resistance Inactivation Pathogenic microorganisms

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化学键参数和原子半径差与BMG合金的GFA关系

蔡安辉,潘冶,孙国雄

《中国工程科学》 2004年第6卷第7期页码 81-87

摘要：

综合大块金属玻璃（BMG）的研究成果，用加权平均原则计算大块金属玻璃的原子半径差比率Δd、原子电负性差比率Δe以及离子率v三个物理参数，以大块金属玻璃的玻璃形成的临界冷却速度R_c作为合金非晶形成能力（GFA）的参数，用Origin 软件分别对上述三个物理参量与R_c的关系进行统计处理时发现：Δd，Δe，及v与BMG的GFA的关系出现极小值现象，不同合金体系极小值的位置不同；玻璃形成能力强的合金体系，其各个组元的原子百分含量、组元原子之间的半径差以及电负性差三者之间的搭配是和谐的。金属玻璃合金的最优成分范围以及各种添加元素的最佳添加量现象可能与这三个物理参量与R_c之间的极小值现象有关。

关键词：化学键参数原子半径差比率大块金属玻璃玻璃形成能力加权平均原则

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基于到达时间差和到达频率差的多层等梯度声速剖面建模与声学定位 Research Article

詹东洲1,王思甜1,蔡守桂1,郑华荣2,徐文2

《信息与电子工程前沿（英文）》 2023年第24卷第1期页码 164-175 doi: 10.1631/FITEE.2100398

摘要：利用传感器节点处信号多普勒频移的导数，提出一种新的使用到达时间差（time difference of arrival，TDOA）和到达频率差（frequency difference of arrival

关键词：水下声学传感器网络；声学定位；声速剖面；到达时间差（TDOA）；到达频率差（FDOA）

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Effect of intestinal ischemia/reperfusion injury on leptin and orexin-A levels

LIN Ji, YAN Guangtao, HAO Xiuhua, ZHANG Kai, GAO Xiaoning, LIAO Jie

《医学前沿（英文）》 2007年第1卷第1期页码 87-92 doi: 10.1007/s11684-007-0017-3

摘要： The aim of this paper is to explore the effect of intestinal ischemia/reperfusion (I/R) injury on leptin and orexin-A levels in peripheral blood and central secretory tissues, and to examine the roles of leptin and orexin-A in acute inflammatory responses. An intestinal I/R injury model of rats was made; the rats were grouped according to the time of after 60 min ischemia. Radioimmunoassay was employed to detect the levels of leptin in serum and adipose tissue and orexin-A levels in plasma and hypothalamus. Reverse transcriptase-polymerase chain reaction was used to detect mRNA expressions of adipose leptin and hypothalamus orexin-A. Compared with the levels before the injury, serum leptin in 60 min ischemia/30 min reperfusion (I60´R30´) group decreased and that of I60´R360´ group increased. Compared with sham-operation group (sham group) after injury, serum leptin level of I60´R360´ group increased, adipose leptin levels of I60´R30´ and I60´R90´ decreased, and adipose leptin in I60´R360´ group increased. After the injury, adipose leptin mRNA expressions of I60´R30´, I60´R240´ and I60´R360´ increased, whereas that of I60´R150´ group decreased as compared with the sham group. There was no significant difference in the protein levels of orexin-A, either between plasma and hypothalamus or between pre- and post-I/R injury. Compared with sham group, hypothalamus orexin-A mRNA expressions of I60´R30´ and I60´R90´ decreased gradually after the injury, with that of I60´R150´ group reaching the lowest, and those of I60´R240´ and I60´R360´ recovering gradually, although they were still significantly lower than that of sham group. Leptin and orexin-A respond to intestinal I/R injury in a time-dependent manner, with leptin responding more quickly than orexin-A does, and both of them may contribute to the metabolic disorders in acute inflammation.

关键词： significant difference intestinal I/R transcriptase-polymerase metabolic central secretory

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一种应用于目标检测和跟踪的和差波束扫描的双周期漏波天线阵列 Research Article

黄棉烽1,2,刘菊华1,2

《信息与电子工程前沿（英文）》 2023年第24卷第4期页码 567-581 doi: 10.1631/FITEE.2200473

摘要：本文提出一种两个基片集成波导（SIW）周期性漏波天线（LWA）组成的天线阵列，该阵列具有和差波束扫描功能，可应用于目标检测和跟踪。阵列由两个具有不同周期的漏波天线组成，其中每个漏波天线通过n=-1空间谐波辐射产生窄波束。这两个漏波天线因为具有不同的周期所以可产生两个不同方向的波束。当对阵列进行同相馈电时，这两个波束将组合成和波束；当对阵列进行反相馈电时，两个波束则组合成差波束。我们设计了集成180°混合网络的阵列，并对其加工与实测。实测结果显示阵列的和波束增益最高可达15.9 dBi，和波束扫描范围为-33.4°至20.8°。在扫描范围内，差波束中的零点方向与和波束的辐射方向角一致，最低的零点深度为-40.8 dB。实测结果表明该天线阵列具有优异的性能，能够为目标检测和跟踪应用提供一种低复杂度和低成本的替代解决方案。

关键词：天线；漏波天线（LWA）；基片集成波导（SIW）；和差波束；目标检测和跟踪

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MHD effect on the critical temperature differences of oscillatory thermocapillary convection in two-layer fluid system

Hulin HUANG, Xiaoming ZHOU,

《能源前沿（英文）》 2010年第4卷第2期页码 155-160 doi: 10.1007/s11708-009-0063-4

摘要： The effect of different directional magnetic fields on critical temperature differences of oscillatory thermocapillary convection in a rectangular cavity with differentially heated side walls filled with two viscous, immiscible, incompressible fluids is simulated in the absence of gravity. In this two-layer fluid system, the upper layer fluid is the electrically non-conducting encapsulant boron oxide (BO), while the lower one is the electrically conducting molten indium phosphide (InP). The interface between the two fluids is assumed to be flat and non-deformable. The computational results show that all the magnetic fields along the , and directions can delay the transition from steady convection to oscillatory convection, and critical temperature differences increase with an increasing Hartmann number. Furthermore, the effect of a magnetic field along the direction is strongest, followed by that along the direction, and that along the direction is the weakest for the same intensity of the magnetic field.

关键词： magnetohydrodynamic magnetic fields thermocapillary convection critical temperature difference oscillatory convection two-layer fluid system

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Abnormal glycosylated hemoglobin as a predictive factor for glucose metabolism disorders in antipsychotic treatment

XU Leping, JI Juying, DUAN Yiyang, SHI Hui, ZHANG Bin, SHAO Yaqin, SUN Jian

《医学前沿（英文）》 2007年第1卷第3期页码 316-319 doi: 10.1007/s11684-007-0061-z

摘要： The aim of this study was to observe the changes in glucose metabolism after antipsychotic (APS) therapy, to note the influencing factors, as well as to discuss the relationship between the occurrence of glucose metabolism disorders of APS origin and abnormal glycosylated hemoglobin (HbAc) levels. One hundred and fifty-two patients with schizophrenia, whose fasting plasma glucose (FPG) and 2-h plasma glucose (2hPG) in the oral glucose tolerance test (2HPG) were normal, were grouped according to the HbAc levels, one normal and the other abnormal, and were randomly enrolled into risperidone, clozapine and chlorpromazine treatment for six weeks. The FPG and 2hPG were measured at the baseline and at the end of the study. In the group with abnormal HbA1c and clozapine therapy, 2HPG was higher after the study [(9.5±1.8) mmol/L] than that before the study [(7.2±1.4) mmol/L] and the difference was statistically significant (〈0.01). FPG had no statistically significant difference before and after the study in any group (〉0.05). HbAc levels and drugs contributing to 2HPG at the end of study had statistical cross-action (〈0.01). In the abnormal HbAc group, 2HPG after the study was higher in the clozapine treatment group [(9.5±1.8) mmol/L] than in the risperidone treatment group [(7.4±1.7) mmol/L] and the chlorpromazine treatment group [(7.3±1.6) mmol/L]. The differences were statistically significant (〈0.01). In the normal HbAc group there was no statistically significant difference before and after the study in any group (〉0.05). 2HPG before [(7.1±1.6) mmol/L] and after the study [(8.1±1.9) mmol/L] was higher in the abnormal HbAc group than in the normal HbAc group [(6.2±1.4) mmol/L (6.5±1.4) mmol/L] with the difference being statistically significant (〈0.01 〈0.001). As compared with normal HbAc group, the relative risk (RR) of glucose metabolism disease occurrence was 4.7 in the abnormal HbAc group with the difference being statistically significant (〈0.001). Patients with abnormal HbAc are more likely to have a higher risk of having glucose metabolism disorders after APS treatment.

关键词： significant difference occurrence hemoglobin risperidone treatment abnormal