检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

鹤峰磷矿在硫、磷混酸中的溶解动力学

化工矿物与加工 2008年第9期37卷 4-6页

作者：谭志斗谷晋川西华大学能源与环境学院

对鹤峰磷矿在硫、磷混酸中的溶解动力学进行了研究,考查了硫酸质量分数及反应温度对酸解过程的影响;选用考虑了自阻化因素的德罗兹多夫方程ln100/(100-Kp)-βKp%=kt描述酸解过程的动力学。研究结果表明:鹤峰磷矿在硫、磷混酸中的反应速... 详细信息

对鹤峰磷矿在硫、磷混酸中的溶解动力学进行了研究,考查了硫酸质量分数及反应温度对酸解过程的影响;选用考虑了自阻化因素的德罗兹多夫方程ln100/(100-Kp)-βKp%=kt描述酸解过程的动力学。研究结果表明:鹤峰磷矿在硫、磷混酸中的反应速率常数随温度升高而增加,随硫酸质量分数的增加而减小。该反应属于扩散控制,平均反应活化能约为32.7 kJ/mol。

关键词：鹤峰磷矿硫磷混酸酸解动力学

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

教师应如何对待外语学习者的错误

广西民族学院学报（哲学社会科学版） 2006年第4期28卷 162-165页

作者：陈金红广西民族大学外国语学院

对外语学习者的错误类型及原因进行分析,并在此基础上提出在中国外语教学环境下教师对待学习者错误的积极态度和可行方法。

关键词：外语学习错误态度方法

一种基于空间滤波的红外小目标检测算法及其应用

在线全文

学校读者我要写书评

暂无评论

红外与毫米波学报 2007年第3期26卷 209-212页

作者：罗军辉姬红兵刘靳西安电子科技大学电子工程学院陕西西安710071

针对红外探测系统中单帧红外图像中的小目标检测问题,在分析红外场景模型的基础上,提出了一种基于自适应噪声平滑和空间滤波的背景杂波抑制算法.该方法对于起伏背景下红外小目标的检测有良好的性能,且具有目标信息损失小的优点.同时,利... 详细信息

针对红外探测系统中单帧红外图像中的小目标检测问题,在分析红外场景模型的基础上,提出了一种基于自适应噪声平滑和空间滤波的背景杂波抑制算法.该方法对于起伏背景下红外小目标的检测有良好的性能,且具有目标信息损失小的优点.同时,利用ADSP-TS201S高性能数字信号处理器实现了该算法,并成功应用到某全向红外搜索跟踪系统中.实验结果表明,在低信噪比情况下,算法有很好的检测性能.

关键词：小目标检测空间滤波 ADSP-TS201S处理器全向红外搜索跟踪系统

Low-frequency blue energy harvesting for sustainable and active anticorrosion

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第9期16卷 11871-11877页

作者： Miaomiao Cui Yawei Feng Hao Wu Yuankai jin Wanbo Li Zuankai Wang Department of Mechanical Engineering City University of Hong KongHong KongChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China Interdisciplinary Research Center for Engineering Science School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Engineering materials serving in marine surroundings are inevitably *** corrosive marine conditions can also be utilized to harvest kinetic ocean wave energy to solve this *** water–solid triboelectrification to harvest lowfrequency wave energy for active anticorrosion is *** techniques are efficient in harnessing environmental energy with frequencies higher than 3 Hz,whereas the dominated ocean waves with optimal wave spectral density fluctuate from 0.45 to 1.5 ***,we proposed a highly efficient and sustainable blue energy-powered cathodic protection(BECP)strategy by fusing water–solid triboelectric nanogenerators and cathodic protection *** the highly efficient triboelectrification between the moving water and hydrophobic fluorinated ethylene propylene tube,we developed the built-in power module,enabling the harvest of ocean wave energy lower than 1.5 *** generated volumetric current density is 28.9 mA·m^(-3),5–20 times higher than the values of the reported ***,the proposed BECP performs comparably to conventional cathodic protection in corrosion ***,the proposed approach can be easily applied to ships,buoys,and other offshore platforms to simultaneously realize blue energy harvesting and engineering material protection,providing an alternative to traditional active protection technology.

关键词： corrosion inhibition blue energy harvesting triboelectric nanogenerator cathodic protection

Superior gallstone dissolubility and safety of tert-amyl ethyl ether over methyl-tertiary butyl ether

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

World Journal of Gastroenterology 2019年第39期25卷 5936-5952页

作者： Dong Do You Suk Joon Cho Ok-Hee Kim jin Sook Song Kyu-Seok Hwang Sang Chul Lee Kee-Hwan Kim Ho Joong Choi Ha-Eun hong Haeyeon Seo Tae Ho hong Jung Hyun Park Tae Yoon Lee Joseph Ahn Jae-Kyung Jung Kwan-Young Jung Say-June Kim Department of Surgery St.Vincent's HospitalCollege of MedicineThe Catholic University of KoreaSeoul 16247South Korea College of Pharmacy Chungbuk National UniversityCheongju 28644South Korea Department of Surgery Seoul St.Mary’s HospitalCollege of Medicinethe Catholic University of KoreaSeoul 06591South Korea Catholic Central Laboratory of Surgery Institute of Biomedical IndustryCollege of Medicinethe Catholic University of KoreaSeoul 06591South Korea Bio and Drug Discovery Division Korea Research Institute of Chemical TechnologyDaejeon 34114South Korea Department of Surgery Daejeon St.Mary's HospitalCollege of Medicinethe Catholic University of KoreaSeoul 34943South Korea Department of Surgery Uijeongbu St.Mary's HospitalCollege of Medicinethe Catholic University of KoreaSeoul 11765South Korea Department of Biomedicine and Health Science College of Medicinethe Catholic University of KoreaSeoul 06591South Korea Department of Surgery Eunpyeong St.Mary’s HospitalCollege of Medicinethe Catholic University of KoreaSeoul 03312South Korea Department of Medicinal Chemistry and Pharmacology University of Science and TechnologyDaejeon 34113South Korea

BACKGROUND The use of methyl-tertiary butyl ether(MTBE)to dissolve gallstones has been limited due to concerns over its toxicity and the widespread recognition of the safety of laparoscopic *** adverse effects of MTBE are largely attributed to its low boiling point,resulting in a tendency to ***,if there is a material with a higher boiling point and similar or higher dissolubility than MTBE,it is expected to be an attractive alternative to *** To determine whether tert-amyl ethyl ether(TAEE),an MTBE analogue with a relatively higher boiling point(102°C),could be used as an alternative to MTBE in terms of gallstone dissolubility and *** The in vitro dissolubility of MTBE and TAEE was determined by measuring the dry weights of human gallstones at predetermined time intervals after placing them in glass containers with either of the two *** in vivo dissolubility was determined by comparing the weights of solvent-treated gallstones and control(dimethyl sulfoxide)-treated gallstones,after the direct infusion of each solvent into the gallbladder in both hamster models with cholesterol and pigmented *** The in vitro results demonstrated a 24 h TAEE-dissolubility of 76.7%,56.5%and 38.75%for cholesterol,mixed,and pigmented gallstones,respectively,which represented a 1.2-,1.4-,and 1.3-fold increase in dissolubility compared to that of *** the in vitro experiment,the 24 h-dissolubility of TAEE was 71.7%and 63.0%for cholesterol and pigmented gallstones,respectively,which represented a 1.4-and 1.9-fold increase in dissolubility compared to that of *** addition,the results of the cell viability assay and western blot analysis indicated that TAEE had a lower toxicity towards gallbladder epithelial cells than *** We demonstrated that TAEE has higher gallstone dissolubility properties and safety than those of *** such,TAEE could present an attractive alternative to MTBE if our findings

关键词： Tert-amyl ethyl ether Gallstones Methyl-tert-butyl ether Contact litholytic agent

关于当前我国小学教育本科专业人才培养策略的思考

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

教师教育研究 2007年第2期19卷 38-40页

作者：丁锦宏南通大学教育科学学院江苏南通226007

小学教师是基础教育的“基础”,该专业涉及面广量人,其人才培养质量直接和间接影响到国家根本利益和千家万户的孩子成长。文章根据小学教师教育专业的特殊性,从“教师标准”、“学籍管理”、“课程设置”、“培养时序”4个方面,阐述了... 详细信息

小学教师是基础教育的“基础”,该专业涉及面广量人,其人才培养质量直接和间接影响到国家根本利益和千家万户的孩子成长。文章根据小学教师教育专业的特殊性,从“教师标准”、“学籍管理”、“课程设置”、“培养时序”4个方面,阐述了该专业的人才培养模式问题,尤其是提出了颠覆教育类课程设置的时序“路线图”的观点。

关键词：小学教育专业教师教育

Roles of cyclooxygenase-2 in microvascular endothelial cell proliferation induced by basic fibroblast growth factor

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2008年第24期121卷 2599-2603页

作者： QIAN Rui-zhe YUE Fei ZHANG Guo-ping HOU Li-kun WANG Xin-hong jin Hui-ming Department of Physiology and Pathophysiology Shanghai Medical College Fudan University Shanghai 200032 China

Background The level of basic fibroblast growth factor （bFGF） increases rapidly after cerebral ischemia. However, the molecular mechanisms for the effects of bFGF on cerebral microvascular endothelial cells （cMVECs） have not yet been fully elucidated. In this study, a murine cMVEC line, bEnd.3, was employed to study the effects of bFGF on cyclooxygenase （COX） expression and its downstream effects in cMVECs. Methods After treatment with bFGF, RT-PCR and Western blotting analyses were carried out to evaluate the changes in COX-2 mRNA and protein expression, respectively. MTT assays were performed to measure cell proliferation. The prostaglandin E2 （PGE2） and vascular endothelial growth factor （VEGF） concentrations in the culture medium were measured by enzyme-linked immunosorbent assay （ELISA）. Results COX-2 mRNA and protein expressions in bEnd.3 cells were induced by bFGF in time- and dose-dependent manners. The bFGF-induced COX-2 upregulation led to enhanced PGE2 production by bEnd.3 cells, and this effect was abolished by the selective COX-2 inhibitor NS-398. bFGF also increased VEGF production by bEnd.3 cells, and this effect was blocked by NS-398 and the EP1/2 （PGE2 receptors） antagonist AH6809. Furthermore, exogenous PGE2 increased VEGF production in bend.3 cells, and AH6809 blocked this effect. Conclusion bFGF increases VEGF production in an autocrine manner by increasing COX-2-generated PGE2 in cMVECs and subsequently stimulates MVEC proliferation and angiogenesis.

关键词： cerebral ischemia cerebral microvascular endothelial cell basic fibroblast growth factor cyclooxygenase prostaglandin E2 vascular endothelial growth factor

在线全文

学校读者我要写书评

暂无评论

明月山隧道涌突水处理设计与施工

公路 2007年第2期52卷 182-187页

作者：陈贵红刘传兵林国进四川省交通厅公路规划勘察设计研究院成都市610041 中铁二局集团第二工程有限公司成都市610031

明月山隧道水文地质条件复杂,岩溶地下水发育,施工过程中发生大的涌突水,掌子面最大流量达15万m3/d。设计采用先在突水点设止浆墙,然后再对前方围岩进行全断面深孔预注浆进行堵水,施工实践表明该处理方式是成功的,目前,隧道施工已顺利... 详细信息

明月山隧道水文地质条件复杂,岩溶地下水发育,施工过程中发生大的涌突水,掌子面最大流量达15万m3/d。设计采用先在突水点设止浆墙,然后再对前方围岩进行全断面深孔预注浆进行堵水,施工实践表明该处理方式是成功的,目前,隧道施工已顺利通过突水地段。本次注浆堵水的成功为隧道涌突水的处理积累了经验,可供类似工程借鉴与参考。

关键词：隧道工程岩溶注浆止浆墙

Accurate and broadband manipulations of harmonic amplitudes and phases to reach 256 QAM millimeter-wave wireless communications by time-domain digital coding metasurface

在线全文

学校读者我要写书评

暂无评论

National Science Review 2022年第1期9卷 36-46页

作者： Ming Zheng Chen Wankai Tang Jun Yan Dai Jun Chen Ke Lei Zhang Cheng Zhang jin Yang Lianlin Li Qiang Cheng Shi jin Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronics Peking University National Mobile Communications Research Laboratory Southeast University State Key Laboratory of Millimeter Waves Southeast University Center of Intelligent Metamaterials Pazhou Laboratory

We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding metasurface(TDCM).Using the proposed mechanism and coding strategy,we design and fabricate a millimeter-wave(mmWave) TDCM,which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative *** controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM,experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to33 GHz,even when the coding states are imperfect,which is in good agreement with theoretical *** on the fabricated high-performance TDCM,we further propose and experimentally realize a large-capacity mmWave wireless communication system,where 256 quadrature amplitude modulation,along with other schemes,is *** new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems,and hence can significantly reduce the hardware *** believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.

关键词： metasurface time-domain digital coding accurate and broadband harmonic control 256 QAM millimeter-wave wireless communications