检索结果-南通市图书馆

Hg^0 removal from flue gas over different zeolites modified by Fe Cl_3

维普期刊数据库评论

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 Environmental Sciences 2015年第2期27卷 110-117页

作者： hao Qi Wenqing Xu Jian Wang li Tong Tingyu Zhu Beijing Engineering Research Center of Process Pollution Control Institute of Process Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

The elemental mercury removal abilities of three different zeolites（Na A, Na X, HZSM-5）impregnated with iron（Ⅲ） chloride were studied on a lab-scale fixed-bed reactor. X-ray diffraction, nitrogen adsorption porosimetry, Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy, and temperature programmed desorption（TPD） analyses were used to investigate the physicochemical properties. Results indicated that the pore structure and active chloride species on the surface of the samples are the key factors for physisorption and oxidation of Hg0, respectively. Relatively high surface area and micropore volume are beneficial to efficient mercury adsorption. The active Cl species generated on the surface of the samples were effective oxidants able to convert elemental mercury（Hg0）into oxidized mercury（Hg2＋）. The crystallization of Na Cl due to the ion exchange effect during the impregnation of Na A and Na X reduced the number of active Cl species on the surface, and restricted the physisorption of Hg0. Therefore, the Hg0 removal efficiencies of the samples were inhibited. The TPD analysis revealed that the species of mercury on the surface of Fe Cl3–HZSM-5 was mainly in the form of mercuric chloride（Hg Cl2）, while on Fe Cl3–Na X and Fe Cl3–Na A it was mainly mercuric oxide（HgO）.

关键词： Mercury Zeolite Flue gas Adsorption Iron chloride HZSM-5

化学遗传学技术在抑郁症神经环路研究中的应用

在线全文

学校读者我要写书评

暂无评论

中华行为医学与脑科学杂志 2024年第6期33卷 554-559页

作者：李绍炜李节惠张明宽张浩胡明会陈丹徐凯勇李自发耿希文魏盛山东中医药大学中医学院济南250355 胜利油田中心医院东营257000 山东中医药大学中医药经典理论教育部重点实验室山东中医药大学中医药与脑科学交叉学科研究平台济南250355

化学遗传学技术是一种通过改变受体特异性和亲和力来调节细胞活性与功能的受体-配体系统的技术,其通过特异性地调控神经元及神经环路精准调控神经。目前,该技术在神经环路研究中应用十分广泛。本文主要简述化学遗传学技术在抑郁症神经... 详细信息

化学遗传学技术是一种通过改变受体特异性和亲和力来调节细胞活性与功能的受体-配体系统的技术,其通过特异性地调控神经元及神经环路精准调控神经。目前,该技术在神经环路研究中应用十分广泛。本文主要简述化学遗传学技术在抑郁症神经环路研究中的应用与进展,梳理该技术在腹侧被盖区、伏隔核、前额叶皮质、海马、外侧缰核等几个与抑郁症发生密切相关的脑区中的应用,讨论化学遗传学技术作为一种精准调控神经活动的技术在未来研究中的潜力和挑战,以期为化学遗传学技术在抑郁症神经环路研究提供可靠的思路和方向。

关键词：化学遗传学技术神经环路抑郁症神经调控

Preparation and Characterization of Polyborosiloxanes and Their Blends with Phenolic Resin as Shapeable Ceramic Precursors

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2014年第2期32卷 187-196页

作者： Hong-ying Zhao 赵京波 hao li Tong Zhao Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Laboratory of Advanced Polymer Materials Institute of Chemistry Chinese Academy Science

Two polyborosiloxanes （PBSis） with char yield up to 74.13% at 800 ℃ were synthesized by the direct polycondensation of boric acid with phenyltrimethoxysilane in diglyme. The PBSis were characterized by gel permeation chromatography, IR spectroscopy as well as ^1H-, ^29Si- and ^11B-NMR. PBSi modified phenol-formaldehyde resins （PBSi/PFs） were prepared at different PBSi/PF mass ratios and were cured at 150 ℃. The PBSi/PFs were characterized by IR spectroscopy, scanning electron microscopy, thermogravimetric analysis and tensile test. The results revealed that the cured PBSi/PFs had sea-island morphology and higher char yield than the common PF. PBSi/PF blend with PBSi/PF mass ratio of 0.4：1 had char yield up to 70.83% at 800 ℃. The PBSi/PFs had tensile strength similar to PF. The ceramization of PBSi/PFs was also studied. The silicon boron oxycarbide （SiBOC） ceramics formed were characterized by IR spectroscopy and elemental analysis. This method provided a valuable way to prepare easily shapeable polymer blends as ceramic precursors.

关键词： Polyborosiloxane Phenolic resin Preparation Ceramic precursors SiBOC ceramics.

Analysis of in-bore magnetic field in C-shaped armature railguns

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2019年第1期15卷 83-88页

作者： Qiang Yin He Zhang hao-jie li Yu-xin Yang Ministerial Key Laboratory of ZNDY Nanjing University of Science and Technology

In order to analysis the distribution characteristics of in-bore magnetic field for C-shaped armature electromagnetic railgun, a computational model considering dynamic contact pressure is established. By solving the dynamic equation, the in-bore motion characteristics of the armature are obtained. The distribution of current in the rail and armature is analyzed based on the magnetic diffusion equation and Ampere’s law. On this basis, three simulation models are proposed, which correspond to static state,motion state and motion state considering the velocity skin effect. The magnetic field of the investigated points along the central axes of the armature front end are obtained. The results show that, in static state,the peak magnetic flux density of each investigated point is greater than the other two states. Velocity skin effect leads to a decrease in peak magnetic flux density. The change of motion state has little influence on the peak magnetic flux density of the investigated point that far away from the armature. The calculated results can be used in the electromagnetic shielding design of intelligent ammunition.

关键词： Railgun C-shaped armature Magnetic flux density

基于特征提取的铝铸件X射线探伤图像缺陷评级技术

在线全文

学校读者我要写书评

暂无评论

特种铸造及有色合金 2024年第5期44卷 605-613页

作者：吴楚澔侯明君李蒙计效园房宇孙晓龙李沁阳董淏李宁周建新华中科技大学材料成形与模具技术全国重点实验室武汉430074 新江科技(江苏)有限公司河源517001

针对铝铸件X射线探伤图像人工缺陷评级方法存在的评级结果不稳定、量化困难等问题,设计了一个基于特征提取算法的铸件缺陷评级系统。首先,通过分析特征参数与缺陷级别间的关系,选择面积作为气孔、夹杂、缩孔和缩松的评级指标,并对照国... 详细信息

针对铝铸件X射线探伤图像人工缺陷评级方法存在的评级结果不稳定、量化困难等问题,设计了一个基于特征提取算法的铸件缺陷评级系统。首先,通过分析特征参数与缺陷级别间的关系,选择面积作为气孔、夹杂、缩孔和缩松的评级指标,并对照国标图谱建立缺陷评级量化体系。然后,对X射线图像进行预处理、边缘检测、轮廓提取和量化计算,并依据所建立体系进行评级;最后开发出一个集成上述功能的自动缺陷评级系统。经验证,该系统与专家评片结果存在±1级的误差。该系统能在一定程度上保证评级品质,便于实现铸件的品质监测。

关键词：铝铸件 X射线图像缺陷评级图像处理特征提取

维普期刊数据库博看期刊

Synthesis of mesoporous γ-AlOOH@Fe_3O_4 magnetic nanomicrospheres

在线全文

学校读者我要写书评

暂无评论

Particuology 2012年第6期10卷 751-758页

作者： Yuanyuan Zheng Shengfu Ji Hongfei liu Ming li hao Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Mesoporous γ-AIOOH@Fe3O4 magnetic nanomicrospheres were synthesized using superparamagnetic Fe304 nanoparticles as the core and aluminum isopropoxide （ALP） as the aluminum source. The obtained magnetic nanomicrospheres were characterized by X-ray powder diffraction （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, N2 adsorption-desorption and vibrating sample magnetometry （VSM）. The effects of preparation parameters such as hydrolysis time of AIP, concentration of AlP and coating layer number on microspheres were investigated. The results indicated that the mesoporous γ-AIOOH@Fe3O4 magnetic nanomicrospheres consisted of a mesoporous γ-AIOOH shell and a Fe3O4 magnetic core. The diameter of γ-AIOOH@Fe3O4 nanomicrospheres was about 200 nm, the thickness of mesoporous γ-AIOOH shell was about 5 nm and the average pore size was 3.8 nm. The thickness of the mesoporous γ-AIOOH shell could be controlled via layer-by-layer coating times. The formation mechanism of the mesoporous γ-AIOOH shell involved a ＂chemisorption-hydrolysis＂ process.

关键词： Magnetic nanomicrospheres Fe3O4 γ-AIOOH shellMesoporousHydrolysis

Effect of template on catalytic performance of La_(0.7)Ce_(0.3)Ni_(0.7)Fe_(0.3)O_3 for ethanol steam reforming reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2019年第6期37卷 594-601页

作者： Ping Yang Ning li Junjiang Teng Jian Wu hao Ma College of Chemical Engineering Guangdong University of Petrochemical Technology College of Chemical Engineering Xiangtan University

Perovskite-type oxides La_(0.7)Ce_(0.3)Ni_(0.7)Fe_(0.3)O_3(LCNF) were synthesized by polystyrene colloidal crystal templating(LCNF-CCT) and polystyrene polymer templating(LCNF-PS) through co-precipitation. The structure and physicochemical properties of the obtained oxides were investigated by scanning electron microscopy, X-ray diffraction, N_2 adsorption-desorption, Fourier transform infrared spectrometry, H_2 temperature-programmed reduction and H_2 temperature-programmed desorption, as well as X-ray photoelectron spectroscopy. The results show that the as-synthesized LCNF-CCT perovskite possesses large specific surface area and regular pore size distribution. In addition, the formation of additional oxygen vacancies on the surface favors the migration of lattice oxygen from the bulk phase to the surface and production of more metallic sites, thus improving the activity and resistance to carbon deposition of catalysts in ethanol steam reforming reaction.

关键词： La0.7Ce0.3Ni0.7Fe0.3O3 Polystyrene colloidal crystal templating Polystyrene polymer templating Ethanol steam reforming Catalytic performance Rare earths

虎杖多糖中蛋白去除工艺及多糖的抗炎作用研究

在线全文

学校读者我要写书评

暂无评论

中南药学 2024年第8期22卷 1999-2005页

作者：罗励耕王丹孟宪群侯昊良黄政浩辽宁中医药大学药学院辽宁大连116600

目的优化虎杖多糖提取工艺,研究其对RAW264.7细胞活性的影响以及在脂多糖诱导的炎症过程中的作用机制。方法用Sevage法对虎杖多糖粗提取物中游离蛋白进行处理,然后进行单因素实验,最后利用响应面法筛选虎杖多糖提取及除蛋白方案。将RAW2... 详细信息

目的优化虎杖多糖提取工艺,研究其对RAW264.7细胞活性的影响以及在脂多糖诱导的炎症过程中的作用机制。方法用Sevage法对虎杖多糖粗提取物中游离蛋白进行处理,然后进行单因素实验,最后利用响应面法筛选虎杖多糖提取及除蛋白方案。将RAW264.7细胞分为正常组和不同浓度虎杖多糖组(5、10、20、40、80、120μg·mL^(-1)),采用CCK-8试剂盒检测虎杖多糖对细胞活力的影响。将RAW264.7细胞分为空白组,模型组(100μg·L^(-1)脂多糖),不同浓度给药组(20、40、80μg·mL^(-1)虎杖多糖溶液),采用EliSA试剂盒检测肿瘤坏死因子-α(TNF-α)、白细胞介素-(IL-6)分泌水平;采用Western blot法检测TLR4、MyD88、NF-κBp65蛋白表达水平。结果筛选得虎杖多糖最优提取方案为Sevage试剂与供试液体积比1∶4、振摇强度8档、振摇时间12 min、除蛋白4次。虎杖多糖质量浓度在20~40μg·mL^(-1)内使细胞活力显著提升,对RAW264.7细胞生长有明显促进作用。与空白组相比,模型组细胞活力升高,TNF-α和IL-6分泌水平及TLR4、NF-κBp65和MyD88蛋白表达水平显著升高,表明巨噬细胞炎症模型构建成功。与模型组相比,虎杖多糖20、40、80μg·mL^(-1)组RAW264.7细胞活力显著降低。此外,在细胞上清液中发现TNF-α和IL-6分泌水平明显减少,并且TLR4、MyD88和NF-κBp65蛋白表达水平也显著降低。结论虎杖多糖可以减少脂多糖诱导的RAW264.7细胞中TNF-α和IL-6分泌,抑制NF-κB信号通路可能是其发挥抗炎作用的一种机制。

关键词：虎杖多糖响应面法 RAW264.7细胞脂多糖炎症因子 NF-κB信号通路

Theoretical and Numerical Studies on the Coupling Deformation of Global Lateral Buckling and Walking of Submarine Pipeline

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2023年第6期22卷 1516-1528页

作者： liU Run hao Xintong li Chengfeng li Qingxin YU Zheng Zhao Dang State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

Buckling initiation devices/techniques,including sleepers,distributed buoyancy,snake lay,and residual curvature method(RCM),have recently been widely applied in *** initiated buckles may induce a long pipeline to transform into multiple short pipeline segments,which promote the occurrence of pipeline ***,a pipeline,which is designed to buckle laterally,may laterally and axially displace over time when subjected to repeated heating and cooling *** study aims to reveal the coupling mechanism of pipeline walking and global lateral ***,an analytic solution is proposed to estimate the walking of pipeline segments between two adjacent ***,the sensitivity of this method to heating and cooling cycles is *** show the applicability of the proposed walking analytical solution of buckling ***,an influence analysis of walking on global buckling,including the capacity of buckling initiation,buckling amplitude,buckling mode,and failure assessment of the buckling pipeline,is *** results reveal that the effect of walking on the buckling axial force is ***,pipeline walking will aggravate the asymmetry of the pipeline buckling and the failure parameters of the pipeline during the post-buckling.

关键词： submarine pipeline global lateral buckling pipeline walking coupling deformation analytic solution