全文获取类型
收费全文 | 239篇 |
免费 | 8篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 2篇 |
综合类 | 1篇 |
化学工业 | 55篇 |
金属工艺 | 4篇 |
机械仪表 | 13篇 |
建筑科学 | 18篇 |
矿业工程 | 1篇 |
能源动力 | 23篇 |
轻工业 | 17篇 |
水利工程 | 7篇 |
石油天然气 | 3篇 |
无线电 | 16篇 |
一般工业技术 | 42篇 |
冶金工业 | 12篇 |
自动化技术 | 36篇 |
出版年
2024年 | 2篇 |
2023年 | 5篇 |
2022年 | 11篇 |
2021年 | 17篇 |
2020年 | 18篇 |
2019年 | 8篇 |
2018年 | 15篇 |
2017年 | 10篇 |
2016年 | 14篇 |
2015年 | 9篇 |
2014年 | 16篇 |
2013年 | 24篇 |
2012年 | 14篇 |
2011年 | 20篇 |
2010年 | 15篇 |
2009年 | 9篇 |
2008年 | 9篇 |
2007年 | 2篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1994年 | 1篇 |
1989年 | 2篇 |
1984年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
排序方式: 共有250条查询结果,搜索用时 15 毫秒
101.
Jeenat Aslam Irfan Hussain Lone Nagi Radwan Mohammad Mobin Saman Zehra Ruby Aslam 《Journal of Adhesion Science and Technology》2013,27(23):2552-2568
Chemical oxidative polymerization of aniline (AN) and o-toluidine (OT) for the synthesis of copolymer, Poly(AN-co-OT) and its composite with TiO2 nanoparticles, Poly(AN-co-OT)/TiO2 employing ammonium persulfate as an oxidant and HCl as an external dopant were carried out. The homopolymers, Polyaniline and Poly(o-toluidine) were also prepared by following similar method. The synthesized polymers were characterized with FTIR spectroscopy, XRD/SEM/TEM analysis. The anticorrosive coatings were synthesized in dimethyl sulfoxide solution by dissolving synthesized polymers, and then were applied on low-carbon steel (LCS) samples using epoxy binder. The anticorrosive potential of the polymer coatings containing copolymer, copolymer-nanocomposite and homopolymers on LCS was evaluated in 3.5% NaCl at a temperature of 30?°C by open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization measurements. It was observed that the nanocomposite coating increases the protection efficacy by providing better barrier properties against corrosion as compared with neat copolymer and homopolymers coatings. The morphology of the coatings before and after 60 days LCS immersion in 3.5% NaCl solution was determined using SEM. 相似文献
102.
Rasoul Sarraf-Mamoory Saman Nadery Nastaran Riahi-Noori 《Chemical Engineering Communications》2013,200(8):1022-1028
Lithium fluoride powder (LiF) is a white powder with a density of 2.64 gr/cm3 and a melting point of 848°C. This powder has several applications such as flux, glaze, soldering, and aluminum melting process, but one of the most important uses of this powder is its application in dosimetry. The commercial powders currently used for this purpose have average sizes of 5 to 10 micrometers; the objective of this research is to produce LiF powder with nano-metric particle size. In this study, the reaction of LiOH + HF → LiF + H2 O has been selected from among several reactions that were able to produce LiF powder, and some precipitation parameters such as temperature, time, agitation type, and supersaturation degree have been controlled. The morphology, phase analysis, and particle size distribution of the resulting powders were analyzed by SEM, XRD, and LPSA. Finally, lithium fluoride nano-powder was synthesized at a temperature of 25°C, pH about 2–3, reaction time less than 1 s, and agitation by ultrasonic bath. 相似文献
103.
K. Johari N. Saman S. T. Song J. Y. Y. Heng 《Chemical Engineering Communications》2013,200(9):1198-1220
Lignocellulosic coconut wastes such as pith and fiber, which are abundantly available and cheap, have the potential of being used as low-cost biosorbents for heavy metal ion removal. In this study, pristine (CF-Pristine) and NaOH-treated (CF-NaOH) coconut fibers were used as a biosorbent for Hg(II) removal from an aqueous solution. The coconut fiber biosorbent (CFB) was characterized by scanning electron microscopy (SEM) and Fourier transform-infrared (FTIR) spectroscopy. The Hg(II) sorption capacities obtained for CF-Pristine and CF-NaOH were 144.4 and 135.0 mg/g, respectively. Both the equilibrium and kinetic data of Hg(II) sorption onto CFB followed the Langmuir isotherm model and a pseudo-second-order kinetic model, respectively. A further analysis of the kinetic data suggested that the Hg(II) sorption process was governed by both intraparticle and external mass transfer processes, in which film diffusion was the rate-limiting step. These results demonstrated that both pristine- and alkali-treated coconut wastes could be potential low-cost biosorbent alternatives for the removal of Hg(II) from aqueous solutions, such as water containing Hg(II) produced in the oil and gas industry. 相似文献
104.
Dr. Phillip L. van der Peet Dr. Saman Sandanayake Prof. Bevyn Jarrott Prof. Spencer J. Williams 《ChemMedChem》2019,14(5):570-582
We previously reported that a lipophilic N-(4′-hydroxy-3′,5′-di-tert-butylbenzyl) derivative ( 1 ) of the voltage-gated sodium channel blocker mexiletine, was a more potent sodium channel blocker in vitro and in vivo. We demonstrate that replacing the chiral methylethylene linker between the amine and di-tert-butylphenol with an achiral 1,3-propylene linker (to give ( 2 )) maintains potency in vitro. We synthesized 25 analogues bearing the 1,3-propylene linker and found that minor structural changes resulted in pronounced changes in state dependence of blocking human NaV1.2 and 1.6 channels by high-throughput patch-clamp analysis. Compared to mexiletine, compounds 1 and 2 are highly selective NaV1.2 inhibitors and >500 times less potent in inhibiting NaV1.6 channels. On the other hand, a derivative (compound 4 ) bearing 2,6-dimethoxy groups in place of the 2,6-dimethyl groups found in mexiletine was found to be the most potent inhibitor, but is nonselective against both channels in the tonic, frequency-dependent and inactivated states. In a kindled mouse model of refractory epilepsy, compound 2 inhibited seizures induced by 6 Hz 44 mA electrical stimulation with an IC50 value of 49.9±1.6 mg kg−1. As established sodium channel blockers do not suppress seizures in this mouse model, this indicates that 2 could be a promising candidate for treating pharmaco-resistant epilepsy. 相似文献
105.
Can sesame consumption improve blood pressure? A systematic review and meta‐analysis of controlled trials 下载免费PDF全文
Hossein Khosravi‐Boroujeni Elham Nikbakht Ernesta Natanelov Saman Khalesi 《Journal of the science of food and agriculture》2017,97(10):3087-3094
Hypertension is a major risk factor for cardiovascular disease, myocardial infarction, stroke and renal failure. Sesame consumption may benefit blood pressure (BP ) owing to its high polyunsaturated fatty acid, fibre, phytosterol and lignan contents. To clarify this, a systematic review and meta‐analysis of controlled trials was conducted. The PubMed (MEDLINE ), Cumulative Index to Nursing and Allied Health Literature (CINAHL ) and Cochrane Library (Central) databases were systematically searched until August 2016. Eight controlled trials with a total of 843 participants met the eligibility criteria. A random effect meta‐analysis showed that sesame consumption can reduce systolic BP (?7.83 mmHg , 95% CI : ?14.12, ?1.54; P < 0.05, I 2 = 99%) and diastolic BP (?5.83 mmHg, 95% CI: ?9.58, ?2.08; P < 0.01, I 2 = 98%). To reduce the heterogeneity, the meta‐analysis was limited to high methodology quality trials (n = 4), which resulted in a significant reduction in systolic BP (?3.23 mmHg, 95% CI: ?5.67, ?0.79; I 2 = 33%) and a non‐significant reduction in diastolic BP (?2.08 mmHg, 95% CI: ?4.85, 0.69; I 2 = 62%). This study concluded that sesame consumption can reduce systolic and diastolic BP. However, further investigations with larger sample sizes and better methodology quality are required to confirm the BP‐lowering effect of sesame consumption. © 2017 Society of Chemical Industry 相似文献
106.
Neighbor-based collaborative filtering is one of the most practical recommendation approaches that is renowned because of its simplicity and explanation. However, the big limitation is its high computational complexity. It is demonstrated that clustering-based algorithms, that restrict the neighborhood space, speed up the recommendation process at the price of lower accuracy. We propose a new algorithm, called TasteMiner that efficiently learns partial users taste to restrict the neighborhood space. We frame TasteMiner as a method for neighborhood collaborative filtering, and show its effectiveness compared to previous algorithms 相似文献
107.
The coconut pith biosorbents were prepared by modifying coconut pith (CP) with sodium hydroxide and bis(triethoxysilylpropyl) tetrasulfide to enhance its sorption capacity and selectivity toward silver ion [Ag(I)]. It was found that the Ag(I) sorption capacity of pure CP, CP modified with sodium hydroxide, and CP modified with bis(triethoxysilylpropyl) tetrasulfide was 0.50, 0.48, and 0.62 mmol/g, respectively. The Ag(I) equilibrium data were best fitted to the Langmuir isotherm model, whereas the kinetic data obeyed the pseudo-second-order kinetic model with the anticipation of the film diffusion as the rate-limiting step. The sorption process was generally governed by a combination of physical and chemical sorption mechanisms. The Ag(I) sorption capacity and selectivity of coconut pith biosorbents were low as compared with other metal ions. 相似文献
108.
Sabbaghpour S Naghashzadehgan M Javaherdeh K Haddad OB 《Water science and technology》2012,65(9):1564-1569
In this paper a new meta-heuristic approach based on the nature of honey bees mating has been used for the calibration of a real city in the north of Iran named Langarud. This city has a population of nearly 68,000 people and about 43,000 water consumers. Langarud's area is about 900 km(2). The method was used to determine the Hazen-Williams roughness factor of the main pipes of the town and a correction factor for the nodal demands in the main nodes of the network. 相似文献
109.
Moments of generalized order statistics appear in several areas of science and engineering. These moments are useful in studying properties of the random variables which are arranged in increasing order of importance, for example, time to failure of a computer system. The computation of these moments is sometimes very tedious and hence some algorithms are required. One algorithm is to use a recursive method of computation of these moments and is very useful as it provides the basis to compute higher moments of generalized order statistics from the corresponding lower-order moments. Generalized order statistics provides several models of ordered data as a special case. The moments of generalized order statistics also provide moments of order statistics and record values as a special case. In this research, the recurrence relations for single, product, inverse and ratio moments of generalized order statistics will be obtained for Lindley–Weibull distribution. These relations will be helpful for obtained moments of generalized order statistics from Lindley–Weibull distribution recursively. Special cases of the recurrence relations will also be obtained. Some characterizations of the distribution will also be obtained by using moments of generalized order statistics. These relations for moments and characterizations can be used in different areas of computer sciences where data is arranged in increasing order. 相似文献
110.
Product testing is a key ingredient in maintaining the quality of a production process. The production process is considered an efficient process if it is capable of quick identification of faulty products. The items produced by any production process are usually packed and acceptance or rejection of the pack depends upon its conformity to some specified quality level. Generally, the specified quality level is based upon the number of defective items found in the inspected number of items. Such decisions are based upon some rules and usually acceptance of the pack is based upon a fewer number of defective items in the pack. Such questions can be answered by using acceptance sampling plans. The acceptance sampling plans assume the fact that the quality level of the item follows some probability distribution. The sampling plans based upon some classical probability distributions are available but often it happens that the quality behavior of the product does not follow a simple probability model and hence the available sampling plans fail. In this paper, we have developed acceptance sampling plans when the product life follows a general Weibull distribution. The sampling plans have been constructed by considering the crisp and fuzzy behavior of the acceptance probability. These sampling plans have been constructed by assuming an infinite lot size. It has been found that the number of items required for inspection decreases with an increase in some parameters. 相似文献