检索结果-南通市图书馆

Aberration changes of the corneal anterior surface following discontinued use of rigid gas permeable contact lenses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2013年第2期6卷 178-182页

作者： qing Yu Jiang-Xiu Wu He-Ning Zhang Sheng Ye shi-qi dong Chen-Hao Zhang New Vision Eye Clinic

AIM: To record aberrations with a corneal topographic device on the anterior surface of the cornea at different time-points prior to wearing and following discontinued use of rigid gas permeable (RGP) contact lenses. The effect of wearing RGP on the anterior surface of the cornea was discussed to provide guidance for clinical refractive error ***: The study objects were 24 eyes from 24 patients. All patients underwent identical examination procedures prior to lens use, as well as afterwards, including slit-lamp examination, non-contact tonometer measurement, computer optometry and corneal curvature measurement, subjective refraction test, and corneal topography analysis. The patients wore contact lenses everyday for 1 month and then discontinued. Corneal topographies were recorded at certain time points of 30 minutes, 1 day, 3, 7 and 14 days following ***: Total corneal aberration at each time point following discontinued use of RGP contact lenses was less than the time point prior to use. Detailed results were as follows: root mean square (RMS) (pre)=(1.438± 0.328)μm, RMS (30 minutes) =(1.076 ±0.355)μm, RMS (1 day) =(1.362 ±0.402)μm, RMS (3 days) =(1.373 ±0.398)μm, RMS (7 days) =(1.387 ±0.415)μm, and RMS (14 days) = (1.430±0.423)μm. Results showed that at 30 minutes after discontinued use of RGP contact lenses, almost all 2 ndand 3 rd-order aberrations change. Quadrafoil Z10 and spherical Z12 of the 4 th-order were also changed. Alterations to Z5, Z6, and Z12 at 1 day after discontinued use were significant differences compared with the time period prior to RGP use: Z5 and Z6 decreased, and Z12 increased slightly. Z5 and Z6 remained decreased at 3 days after discontinued use, but Z9 and Z10 continued to increase and Z12 returned to levels prior to RGP use. At 14 days after discontinued use, all aberrations were notsignificantly different from the values prior to ***: The use RGP contact lenses greatly reduced total aberration of th

关键词： aberration rigid gas permeable contact lens cornea

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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 Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan qi Xin Zhang Jun Li dong-liang Zhao shi-hai Guo Yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

Joint Effects of Multipollutant Mixtures on Mortality in Chengdu,China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第1期37卷 112-116页

作者： ZHANG Ying TIAN qi qi HU Wen dong ZHANG Shao Bo WANG shi Gong ZHENG Can Jun Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225SichuanChina Yunnan R&D Institute of Natural Disaster on Chengdu University of Information Technology Kunming 650034YunnanChina Chengdu Plain Urban Meteorology and Environment Sichuan Provincial Field Scientific Observation and Research Station Chengdu 610225SichuanChina Chinese Center for Disease Control and Prevention National Institute for Communicable Disease Control and PreventionBeijing 102206China

Significant epidemiological research has revealed that exposure to air pollution is substantially associated with numerous detrimental health consequences^([1-3]).The negative health effects of individual air pollutants(e.g.,fine particulate matter:PM_(2.5);nitrogen dioxide:NO_(2);carbon monoxide,CO;or ozone:O_(3))have been widely explored^([4]).However,humans are constantly exposed to multipollutant mixtures in real life,and biological responses to inhaled pollutants are likely to depend on the interplay of pollutant ***,it is critical and imperative to explore the joint effects of multipollutant mixtures on human beings.

关键词： mixtures monoxide consequences

Investigating Load Regulation Characteristics of a Wind-PV-Coal Storage Multi-Power Generation System

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy Engineering 2024年第4期121卷 913-932页

作者： Zhongping Liu Enhui Sun Jiahao shi Lei Zhang qi Wang Jiali dong Sinopec Star Co. Ltd.Zhengzhou450000China Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology North China Electric Power UniversityBaoding071003China

There is a growing need to explore the potential of coal-fired power plants(CFPPs)to enhance the utilization rate of wind power(wind)and photovoltaic power(PV)in the green energy *** study developed a load regulation model for a multi-power generation system comprising wind,PV,and coal energy storage using realworld *** power supply process was divided into eight fundamental load regulation scenarios,elucidating the influence of each scenario on load *** the framework of the multi-power generation system with the wind(50 MW)and PV(50 MW)alongside a CFPP(330 MW),a lithium-iron phosphate energy storage system(LIPBESS)was integrated to improve the system’s load regulation *** energy storage operation strategy was formulated based on the charging and discharging priority of the LIPBESS for each basic scenario and the charging and discharging load calculation method of LIPBESS auxiliary *** optimization using the particle swarm algorithm,the optimal capacity of LIPBESS was determined to be within the 5.24-4.88 MWh *** an economic perspective,the LIPBESS operating with CFPP as the regulating power source was 49.1% lower in capacity compared to the renewable energy-based storage mode.

关键词： Wind power coal-fired power PV multi-power generation system lithium-iron phosphate energy storage system

Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： Ye TIAN Tielin shi qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

Expression of SNC73, a transcript of the immunoglobulin α-1 gene, in human epithelial carcinomas

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 2007年第16期13卷 2305-2311页

作者： Li-Yi Geng Zheng-Zhen shi qi dong Xin-Han Cai Yan-Ming Zhang Wei Cao Jia-Ping Peng Yong-Ming Fang Lei Zheng Shu Zheng Cancer Institute Zhejiang University School of Medicine Hangzhou 310009 Zhejiang Province China

AIM： To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene （IgA1-H chain）, in human epitheliα-derived tumor cells. METHODS： Total RNAs and cell lysates were prepared from five different human epithelial cell lines derived from lung, stomach, liver, skin, and breast, respectively. RT-PCR and immunoblot analysis of these five cell lines were done. Both RT-PCR and immunochemistry were used to detect the expression of SNC73 in these cell lines. We also examined the expression of SNC73 in normal epithelial cells of colon mucosa by in situ hybridization. RT-PCR and immunoblot analysis were used to determine whether the recombination activating gene1/2 （RAG1 and RAG2） is present. The expression of three immunoglobulin transcription factors, EBF, E2A and Pax5, and the heavy chain of IgA1 and two types of light chains of immunoglobulin （κ and λ） in the aforementioned cell lines were analyzed by RT-PCR and immunochemistry, respectively. All the RT-PCR products were analyzed by sequencing. RESULTS： The results of RT-PCR and immunochemistry showed that both mRNA and protein of SNC73 were expressed in five human epitheliα-derived cancer cell lines. These data were further confirmed in the normal epithelial cells of colon mucosa by in situ hybridization. Also, the heavy chain of IgA1 and κ light chain were detected in these cells, but no λ light chain was observed. Both RAG1 and RAG2 were expressed in these human epitheliα-derived cancer cell lines and the sequence was identical to that expressed in pre-B and pre-T cells. In addition to RAG1 and RAG2, the mRNA in one of the immunoglobulin transcription factors, EBF, was also detected in these cell lines, and Pax5 was only expressed in SW480 cells, but no expression of E2A was observed in all the five cell lines. CONCLUSION： Immunoglobulin A1 is originally expressed and V（D）J recombination machine is also present in non-lymphoid cells, suggesting that V（D）J recombination machine mediates the assembly

关键词： SNC73 Immunoglobulin A1 Epithelial cancer cells Recombination activating gene1/2 Immunoglobulin transcription factor

Projections of summer light rain frequency in typical terrain over eastern China under wind speed constraint

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第6期67卷 1885-1894页

作者： Xuechen dong Daoyi GONG Cuicui shi Institute of Disaster Risk Science Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster MOEFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China School of Systems Science Beijing Normal UniversityBeijing 100875China

The variation in near-surface wind speed is a key dynamic parameter in the orographic effect of precipitation over eastern *** this study,we used the latest high-resolution outputs from six GCMs in CMIP6-HighResMIP to evaluate the performance of high-resolution models in simulating the orographic precipitation characteristics of typical mountainous areas in summer over eastern *** orographic precipitation under warming scenarios was projected and constrained according to observational *** results indicated that during the contemporary climate reference period(1979-2009),although the relationship between model-simulated near-surface wind speed and orographic light rain frequency was consistently stable,the sensitivity of the orographic light rain frequency to surface wind variability was generally underestimated,with a deviation approximately 24.1% lower than the observational *** estimated orographic light rain frequency corrected based on the observed near-surface wind speed under a 1.5℃ warming scenario,was 36.1% lower than that of the contemporary period;this reduction was 8.6 times that without the wind speed constraint(4.2%).The MRI-AGCM3-2-S model,with a longer dataset,demonstrated relatively stable reductions in orographic light rain frequency under different warming scenarios(1.5℃,2℃,3℃,and 4℃)after the application of wind speed *** all cases,the reductions exceeded those for the predictions made without the wind speed constraint.

关键词： Frequency of orographic light rain HighResMIP High-resolution projection Observational constraint Eastern China

Giant bile duct dilatation in newborn:A case report

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第6期12卷 1150-1156页

作者： dong-Wen Quan Peng-Gang Li Xiang-Hua Xu shi-qi Liu The Second Clinical Medical School Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina The First School of Clinical Medicine Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Neonatal Surgery Xi’an Children’s Hospital Affiliated Xi’an Jiaotong UniversityXi’an 710003Shaanxi ProvinceChina

BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical *** born with this condition often experience a poor overall health status,and the disease progresses rapidly,leading to severe biliary obstruction,infections,pressure exerted by the enlarged CBD on abdominal organs,disturbances in the internal environment,and multiple organ *** treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs,making it difficult to separate the bile duct wall from adjacent tissues or to control *** SUMMARY Herein,we present the details of an 11-d-old male newborn who was diagnosed with giant *** patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago,and also because the patient had been experiencing yellowish skin for the past 9 *** abnormal echo in the fetal abdomen was first noticed by the patient’s mother during a routine ultrasound examination at a local hospital,when the patient was at 24 wk+6 d of *** finding raised concerns about the possibility of congenital biliary dilatation(22 mm×21 mm).Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary *** specific treatment was administered for biliary dilatation during this period.A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis,measuring approximately 9.2 cm×7.4 cm×11.3 *** on the CONCLUSION The analysis reveals that prenatal imaging techniques,such as ultrasound and magnetic resonance imaging,play a crucial role in the early diagnosis,fetal prognosis,and treatment plan for giant *** surgery for giant CBD presents certain challenges,including difficulties in separating the cyst wall,anastomosis,and hemos

关键词： Acute cholangitis Congenital biliary dilation Laparoscopic surgery vs Open hepatic duct-jejunostomy Case report

An M-VCUT level set-based data-driven model of microstructures and optimization of two-scale structures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

FRONTIERS OF MECHANICAL ENGINEERING 2024年第4期19卷 26-0页

作者： Shao, Minjie shi, Tielin Xia, qi Huazhong Univ Sci & Technol State Key Lab Intelligent Mfg Equipment & Technol Wuhan 430074 Peoples R China

The optimization of two-scale structures can adapt to the different needs of materials in various regions by reasonably arranging different microstructures at the macro scale, thereby considerably improving structural performance. Here, a multiple variable cutting (M-VCUT) level set-based data-driven model of microstructures is presented, and a method based on this model is proposed for the optimal design of two-scale structures. The geometry of the microstructure is described using the M-VCUT level set method, and the effective mechanical properties of microstructures are computed by the homogenization method. Then, a database of microstructures containing their geometric and mechanical parameters is constructed. The two sets of parameters are adopted as input and output datasets, and a mapping relationship between the two datasets is established to build the data-driven model of microstructures. During the optimization of two-scale structures, the data-driven model is used for macroscale finite element and sensitivity analyses. The efficiency of the analysis and optimization of two-scale structures is improved because the computational costs of invoking such a data-driven model are much smaller than those of homogenization.

关键词： two-scale structure structural optimization M-VCUT level set homogenization radial basis function data-driven TOPOLOGY OPTIMIZATION DESIGN SHAPE