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51.
XUE MEI LUO SHAHANAVAJ KHAN ABDUL MALIK FAHAD M. ALDAKHEEL ANIS AHMAD CHAUDHARY SHOUKI BAZARBASHI FATEMEH TABATABAIE 《Biocell》2022,46(3):759-767
Despite the multiple systematic reviews and meta-analyses accumulating evidence on the preventive effect of calcium supplementation for colorectal cancer, most of the associated adverse effects are not systematically analyzed. The aim of the study is evaluating adverse events associated with calcium supplementation for colorectal cancer prevention through a systematic meta-analysis. We searched Medline, PubMed Central, EMBASE (Excerpta Medica database), Scopus, Cochrane Central Register of Controlled Trials, and Web of Science published in English from database inception up to 31 July 2019. In the current systematic meta-analysis, we included human studies (including cohort studies, clinical trials, case-control studies) on supplementation of calcium in patients with or at risk of colorectal cancer. Assessment of the quality of included studies was performed by Jadad score. Information on the patient population, number of enrolled subjects in each group, dose of calcium supplementation, duration of calcium supplementation, and reported adverse events were gathered. The data were pooled for incidence rates for any adverse event during the study period regardless of causality association. We identified 6 studies, comprising 4583 participants that met the inclusion criteria. Meta-analysis on pooled incidence rates for adverse event during study period showed no statistically significant increased risk for cancer (OR = 0.92, 95% CI: 0.70–1.21, P = 0.577; I2 = 0.0%, P = 0.731), coronary revascularization (OR = 1.12, 95% CI: 0.79–1.59, P = 0.492; I2 = 0.0%, P = 0.957), myocardial infarction (OR = 0.81, 95% CI: 0.34–1.91, P = 0.634; I2 = 67.9%, P = 0.047), stroke (OR = 0.75, 95% CI: 0.42–1.33, P = 0.332, I2 = 0.00%, P = 0.717), Transient Ischemic Attack (TIA) (OR = 1.37, 95% CI: 0.28–6.51, P = 0.692, I2 = 81.9%, P = 0.002), urolithiasis (OR = 1.23, 95% CI: 0.75–2.01, P = 0.410; I2 = 0.0%, P = 0.851), fracture (OR = 0.98, 95% CI: 0.70–1.37, P = 0.938; I2 = 37.8%, P = 0.152) and death (OR = 1.05, 95% CI: 0.71–1.56, P = 0.786, I2 = 12.2%, P = 0.317) in patients receiving calcium supplementation for colorectal cancer prevention compared to control. Based on the results of Egger test, publication bias was not observed among the studies (P = 0.262). The current result of the meta-analysis on human studies reporting adverse events associated with calcium supplementation for the prevention of colorectal cancer demonstrated no statistically significant increased risk for the development of adverse events compared to control groups. 相似文献
52.
KAMRAN KHEIRALIPOUR AHMAD TABATABAEEFAR HOSSEIN MOBLI SHAHIN RAFIEE ALI RAJABIPOUR ALI JAFARI 《Journal of food process engineering》2011,34(2):304-304
Retracted : The following article from Journal of Food Process Engineering, “Hydro‐sorting of Apple Using Terminal Velocity in Water” by Kamran Kheiralipour, Ahmad Tabatabaeefar, Hossein Mobli, Shahin Rafiee, Ali Rajabipour, and Ali Jafari published online on 22 February 2010 in Wiley Online Library ( http://www.onlinelibrary.wiley.com ), has been retracted by agreement between the authors, the Journal's Co‐Editors, M. Elena Castell‐Perez and Rosana Moreira, and Wiley Periodicals, Inc. The retraction has been agreed due to overlap between this article and the following article published in the Transactions of the American Society of Agricultural Engineers (now called Transactions of the American Society of Agricultural and Biological Engineers), “Sorting of Kiwifruit for Quality Using Drop Velocity in Water” by Robert B. Jordan and Christopher J. Clark. Vol. 47:6 (2004): 1991–1998. 相似文献
53.
基于UG平台,以行星轮爬壁机构为研究对象,根据设计要求完成了其所有零部件的结构设计、三维建模及虚拟装配;应用ADAM S对其进行运动仿真,得到位移—时间、角速度—时间的关系曲线,为行星轮爬壁机构的动力学分析提供了科学依据;应用AN SY S软件进行了有限元模态分析,得到了前6阶模态和振型图,使机构的固有频率避开了共振频率,减小了机构的振动。 相似文献
54.
In this paper, a fracture mechanics method was applied for the evaluation of crack behaviour in anisotropic paperboard subjected to biaxial uniform loading. The experiment was performed to determine the crack propagation angle and the fracture strength of paperboard under biaxial loading with the cruciform specimen optimized by FEM simulation. The effects of biaxial loads on the critical stress ratio and crack propagation angle for various inclination angles were investigated. The experimental results were compared with theoretical results, which were calculated by using the Normal Stress Ratio Criteria. The experimental results for crack propagation angle and critical stress show good agreement with theoretical results. 相似文献
55.
AlON nanolayers are synthesized on Al substrate by the irradiation of energetic nitrogen ions using plasma focusing. Samples are exposed to multiple(5, 10, 15, 20 and 25) focus shots. Ion energy and ion number density range from 80 keV to 1.4 MeV and 5.6×1019m-3 to 1.3×1019m-3, respectively. Moreover, the efect of continuous annealing(473 K and 523 K) on an AlN surface layer synthesized with 25 focus shots is also examined. The main features of the X-ray difraction(XRD) patterns with increasing focus shots are:(i) variation in the crystallinity of AlN along(111),(200) and(311) planes,(ii) increasing average crystallite size of AlN(111) plane, and(iii) stress relaxation observed in AlN(111) and (200) planes. The crystallinity of AlN surface layer is comparatively better at 473 K annealing temperature. A broadened difraction peak related to an aluminium oxide phase showing weak crystallinity is observed for 15 focus shots while non-bounded oxides are present in all other deposited layers. Raman and Fourier transform infrared spectroscopy(FTIR) analysis confirm the presence of AlN and Al2O3 for the surface layer annealed at 473 K temperature. Raman analysis shows that the overlapping of AlN and Al2O3 results in the development of residual stresses. Scanning electron microscope(SEM) results demonstrate that the formation of rounded grains(range from 20 nm to 200 nm) and variations in their microstructures features depend on the increasing number of focus shots. Decomposition of larger clusters into smaller ones is observed. 相似文献
56.
Conditions that must be satisfied before the launch of a Space Transportation System (STS) include combinations of ambient temperature and wind speed that are intended to prevent ice formation on the External Tank (ET) and a local air temperature around the STS of 33°F (0.56°C) or less. Nineteen effluent gases are purged or vented from the STS into the launch pad environment, the most significant of these being the cold and negatively buoyant boil-off gaseous oxygen (GOX) from the oxygen tank. Vented into the ambient, this GOX can be wind-carried toward the STS, where it will cool the launch pad environment. This article described a combined three-dimensional (3D) and two-dimensional (2D) computational fluid dynamics (CFD) analysis that investigated this cooling effect. The results of this analysis for a 6-knot (3.09 m/s) west wind and an ambient temperature of 38°F (3.33°C) indicate that the GOX could cool, relative to the ambient, the local air in the vicinity of the STS and the surface of the east Redesigned Solid Rocket Motor (RSRM) by as much as 28°F (15.56°C) and 5 to 6°F (2.78 to 3.33°C), respectively. The large lengths associated with the ET and the east RSRM resulted in Rayleigh numbers that were one to three orders of magnitude larger than those found in literature. 相似文献
57.
ABBAS KHOSHHAL ASGHAR ALIZADEH DAKHEL AHMAD ETEMADI SINA ZERESHKI 《Journal of food process engineering》2010,33(S1):298-313
Artificial neural network (ANN) modeling and several mathematical models were applied to predict the moisture ratio in an apple drying process. Four drying mathematical models were fitted to the data obtained from eight drying runs and the most accurate model was selected. Two sets of ANN modeling were also performed. In the first set, the data obtained from each pilot were modeled individually to compare the ANN predictions with the best mathematical model. In the second set of ANN modeling, the simultaneous effect of all the four input parameters including air velocity, air temperature, the thickness of apple slices and drying time was investigated. The results showed that the ANN predictions were more accurate in comparison with the best fitted mathematical model. In addition, none of the mathematical models are able to predict the effect of the four input parameters simultaneously, while the presented ANN model predicts this effect with a good precision.
Today, modeling of chemical engineering processes is widespread in the process industries. An accurate modeling results in a precise prediction of the products of a process which could be very expensive or even unsafe to evaluate by experimental experiences. Because artificial neural network modeling is more or less proved to be one of the best modelings against mathematical ones, we suggest it to be considered for industrial processes such as drying in the food industry. 相似文献
PRACTICAL APPLICATIONS
Today, modeling of chemical engineering processes is widespread in the process industries. An accurate modeling results in a precise prediction of the products of a process which could be very expensive or even unsafe to evaluate by experimental experiences. Because artificial neural network modeling is more or less proved to be one of the best modelings against mathematical ones, we suggest it to be considered for industrial processes such as drying in the food industry. 相似文献
58.
FARZANA AHMAD MUHAMMAD JAMIL YOUNG JAE JEON LEE JIN WOO JAE EUN JUNG JAE EUN JANG 《Bulletin of Materials Science》2012,35(2):221-231
Sudan black B (SBB) was used to investigate as the nonionic diazo dye-doped in polymer dispersed liquid crystal (PDLC) display, by polymerization-induced phase separation (PIPS) method. The maximum absorbance, contrast ratio, dichroic ratio and the order parameter of nonionic diazo dye in nemetic host (TL203) were investigated using UV?CVis polarized spectroscopy. The orientation of the dye molecules was controlled by electric field, which enabled the contrast ratio of the dye to be obtained by electrically switching. The change occurring on droplet morphologies and electro-optical properties of PDLC film with the change in contents of Sudan black dye and liquid crystals (LC) contents was investigated. We found an increase in LC droplet sizes with the increase of diazo dye and LC contents. Moreover the addition of small amount of nonionic diazo dye reduced the threshold voltage (V $_{\boldsymbol{\rm th}})$ , increased off-state transmittance, enhanced the contrast ratio and decreased the response time of dye-doped PDLC. Additionally the change in transition temperature of LC and changes in LC droplet morphologies with the addition of dye were also observed. Such changes were observed with the images taken by polarized optical microscope (POM). The detail discussions on such behaviours were also made. 相似文献
59.
60.
AHMAD RAHBAR-RANJI 《Sadhana》2014,39(2):511-524
Corrosion is a long-term, inevitable process, lessens the thickness and load carrying capacity of structures. Old steel structures are more vulnerable to buckling, yielding and fracture due to corrosion. In lieu of a detailed analysis, average thickness assumption is employed for general type of corrosion. However, the estimation of load carrying capacity reduction of corroded structures typically need a much higher level of accuracy, since the actual corroded plates would have irregular surfaces. The objective of this article is to determine the effect of general corrosion on reduction of elastic buckling strength of both-sided partially corroded plates with irregular surfaces. Eigenvalue analysis using finite element method is employed for Euler stress calculation of corroded plates. The effects of different influential parameters are investigated and it is found that, aspect ratio of plate, location of corroded area, standard deviation of thickness diminution and concentration of corrosion have influence on reduction of elastic buckling strength. Reduction of elastic buckling strength is very sensitive to the amount of corrosion loss. The higher the amount of corrosion loss, the more reduction of elastic buckling strength. 相似文献