全文获取类型
收费全文 | 430篇 |
免费 | 19篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 183篇 |
金属工艺 | 5篇 |
机械仪表 | 6篇 |
建筑科学 | 25篇 |
能源动力 | 16篇 |
轻工业 | 73篇 |
水利工程 | 3篇 |
武器工业 | 1篇 |
无线电 | 15篇 |
一般工业技术 | 56篇 |
冶金工业 | 7篇 |
自动化技术 | 55篇 |
出版年
2022年 | 17篇 |
2021年 | 31篇 |
2020年 | 8篇 |
2019年 | 9篇 |
2018年 | 13篇 |
2017年 | 15篇 |
2016年 | 11篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 34篇 |
2012年 | 31篇 |
2011年 | 17篇 |
2010年 | 22篇 |
2009年 | 18篇 |
2008年 | 14篇 |
2007年 | 14篇 |
2006年 | 13篇 |
2005年 | 7篇 |
2004年 | 8篇 |
2003年 | 23篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 7篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1973年 | 3篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有450条查询结果,搜索用时 46 毫秒
111.
The results of the investigations on the auto‐thermal combustion of lean gaseous fuels in a recuperative annular double‐layer catalytic converter were reported in the current contribution. Several modifications were proposed to improve the stationary and transient behaviour of the converters. The miniaturized recuperative converter exhibited reduced resistances to the mass and heat transfer and attractive bifurcation changes of a very low combustible content, that is, the histeresis for Tin and Cin and isola for mfin and hg. It was revealed that the utilization of an adiabatic recuperative converter led to an autothermal operation for Tin = 300 K and Cin = 177 ppmv of propane. The inlet fuel mass flow rate range to apply was wider than earlier reported in the literature, that is, 0.63–2.94 × 10?6 kg s?1 for Cin = 200 ppmv. Transient experiments showed that recuperative converter was able to transfer short‐time inlet disturbances of parameters due to the energy accumulation and temporal reversed recuperation counteracting to extinction or to destructive overheating of the catalysts. Stability analysis was performed showing location of folds, stable and unstable branches of solutions for the different parameters of the recuperative converter. A two‐dimensional process model was developed. 相似文献
112.
Magdalena Rudzińska Ewa Flaczyk Ryszard Amarowicz Erwin Wąsowicz Józef Korczak 《European Food Research and Technology》2007,224(3):293-299
The effect of acid (CAH) and enzymatic (CEH) hydrolysates prepared from pork cracklings on the oxidative stability of frozen pork meatballs was investigated. Meatballs were stored at −18 °C for 180, 270 and 360 days during which time peroxide value (PV), TBARS, profiling sensory analysis and cholesterol oxidation products (COPs) were determined. The oxidation products of cholesterol, such as epimers 7-hydroxy, 5,6-epoxy, 7-keto, triol and 25-hydroxy, after transesterification and SPE fractionation, were detected by capillary gas chromatography. CAH and CEH possessed similar antioxidant efficacy. Inhibition activity of cracklings hydrolysates against PV was 38–45%, and against TBARS was 30–39%. The antioxidant properties of CAH and CEH against the oxidation of lipids were poorer than that of BHT. The addition of hydrolysates changed sensory profiles and had a significant (P<0.05) effect on the taste and odour of meatballs. The total COPs in all meatballs increased during storage. 7-Keto-cholesterol was the dominant oxysterol in fresh samples. After 360 days of storage, levels of oxysterols in samples treated with hydrolysates were about 20% lower than that of the control sample. The most toxic derivative, triol-cholesterol, was detected at the lowest level in samples treated with hydrolysates. The protection of BHT against cholesterol oxidation was poorer than that of CEH. 相似文献
113.
Yamini Tak Manpreet Kaur Rajendra Kumar Chirag Gautam Prabhjot Singh Harjeet Kaur Amanpreet Kaur Surekha Bhatia Niraj Kumar Jha Piyush Kumar Gupta Ryszard Amarowicz 《Journal of food science》2022,87(7):2798-2819
Chia seed oil (CSO) has been recently gaining tremendous interest as a functional food. The oil is rich in with polyunsaturated fatty acids (PUFAs), especially, alpha linolenic acid (ALA), linoleic acid (LA), tocopherols, phenolic acids, vitamins, and antioxidants. Extracting CSO through green technologies has been highly efficient, cost-effective, and sustainable, which has also shown to improve its nutritional potential and proved to be eco-friendly than any other traditional or conventional processes. Due to the presence of valuable bioactive metabolites, CSO is proving to be a revolutionary source for food, baking, dairy, pharmaceutical, livestock feed, and cosmetic industries. CSO has been reported to possess antidiabetic, anticancer, anti-inflammatory, antiobesity, antioxidant, antihyperlipidemic, insect-repellent, and skin-healing properties. However, studies on toxicological safety and commercial potency of CSO are limited and therefore the need of the hour is to focus on large-scale molecular mechanistic and clinical studies, which may throw light on the possible translational opportunities of CSO to be utilized to its complete potential. In this review, we have deliberated on the untapped therapeutical possibilities and novel findings about this functional food, its biochemical composition, extraction methods, nutritional profiling, oil stability, and nutraceutical and pharmaceutical applications for its health benefits and ability to counter various diseases. 相似文献
114.
115.
Ryszard Szwaba 《热科学学报(英文版)》2013,22(4):294-303
Control of shock wave and boundary layer interaction continues to attract a lot of attention. In recent decades several methods of interaction control have been investigated. The research has mostly concerned solid (vane type) vortex generators and transpiration methods of suction and blowing. This investigation concerns interaction control using air-jets to generate streamwise vortices. The effectiveness of air-jet vortex generators in controlling separation has been proved in a previous research. The present paper focuses on the influence of the vortex generator diameter on the separation region. It presents the results of experimental investigations and provides new guidelines for the design of air-jet vortex generators to obtain more effective separation control. 相似文献
116.
Maria Tomaszewska Marta Szabat Karolina Zieliska Ryszard Kierzek 《International journal of molecular sciences》2021,22(11)
Influenza A virus (IAV) causes seasonal epidemics and sporadic pandemics, therefore is an important research subject for scientists around the world. Despite the high variability of its genome, the structure of viral RNA (vRNA) possesses features that remain constant between strains and are biologically important for virus replication. Therefore, conserved structural motifs of vRNA can represent a novel therapeutic target. Here, we focused on the presence of G-rich sequences within the influenza A/California/07/2009(H1N1) genome and their ability to form RNA G-quadruplex structures (G4s). We identified 12 potential quadruplex-forming sequences (PQS) and determined their conservation among the IAV strains using bioinformatics tools. Then we examined the propensity of PQS to fold into G4s by various biophysical methods. Our results revealed that six PQS oligomers could form RNA G-quadruplexes. However, three of them were confirmed to adopt G4 structures by all utilized methods. Moreover, we showed that these PQS motifs are present within segments encoding polymerase complex proteins indicating their possible role in the virus biology. 相似文献
117.
The results of experimental investigation of molar heat capacity of [N(C2H5)4]2CuCl4 - ferroelasto-ferroelectric crystals in a wide temperature range are presented. The typical anomaly for the first order phase transition of order-disorder type at 258 K and additional anomaly with maximum at 195 K has been observed. We suggest that the low temperature anomalies of physical properties of [N(C2H5)4]2CuCl4 crystals can be attributed to over critical traces of isomorphous phase transitions (similar to that observed in liquid-gas system). Results of numerical analysis of phenomenological model of phase transition in [N(C2H5)4]2CuCl4 crystals are presented and compared with the experimentally determined temperature dependence of the specific heat and entropy changes. 相似文献
118.
On the basis of demographic projections, it is estimated that the quantity of sewage sludge which will be produced in Poland between 2010 and 2018 will increase from 612.8 thousand tons (dry basis, d.b.) to 706.6 thousand tons (d.b.). Currently, the predominant method for the disposal of this sludge is its storage and agricultural application. However, the legislation taking effect in the next few years will effectively block these avenues of sewage-sludge disposal. Therefore, effective methods of thermal sewage-sludge utilization must be developed. Here we review the state of knowledge and technology in thermal methods for the utilization of municipal sewage sludge to obtain useful forms of energy such as pyrolysis, gasification, combustion, and co-combustion. 相似文献
119.
120.
Ryszard Galus Krzysztof W?odarski Jacek Malejczyk Jaros?aw Jó?wiak 《International journal of molecular sciences》2013,14(7):14333-14345
Our recent in vitro experiments suggest that fluvastatin may influence tyrosinase (key enzyme of melanogenesis) synthesis. The aim of the present study was to verify those findings in experiments, in vitro, in melanoma cell line, and in vivo, in mice. The expression of tyrosinase in B16F10 melanoma cell line, after induction of melanogenesis by UVB irradiation, was examined by Western blot analysis. Afterwards, the effect of fluvastatin on melanin synthesis in hair follicles of C57Bl/6 mice was investigated. The expression of tyrosinase was reduced in the presence of fluvastatin. In mice after anagen induction over the dorsal skin, gel containing fluvastatin in various concentrations was injected subcutaneously, while in part of control groups of mice, gel with placebo was injected. In addition, gel with fluvastatin was injected to four week-old mice (mice in first postnatal anagen) without anagen induction. In extension, injections of gel with fluvastatin or placebo were performed in mice without anagen induction (but after first postnatal anagen). In part of study group of mice (mice after anagen induction and injection of fluvastatin) regrowth of depigmented hair was observed, while in all control groups (mice after injection of placebo), such hair depigmentation over the skin area was not found. In conclusion, this study, for the first time, shows that fluvastatin might affect melanin synthesis in vivo. 相似文献