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991.
Barnett David W.; Bauer Annie M.; Ehrhardt Kristal E.; Lentz Francis E.; Stollar Stephanie A. 《Canadian Metallurgical Quarterly》1996,11(2):95
Discusses childhood problem behaviors within the school setting. Keystone variables are described as those that, if changed, are likely to positively impact the largest set of other significant behaviors, perceptions, or problem environments to most efficiently provide long-term resolution of problem situations. The concept of keystone target variable selection is elaborated for school psychological practice. First, the conceptual and empirical bases for target variable selection are described. Next, keystone variables are further defined, the rationales for keystone variable identification are presented, and pertinent research is examined. Finally, suggestions for identifying keystone variables are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Suh K.S. Ho Gyu Yoon Chang Ryong Lee Okamoto T. Takada T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1999,6(3):282-287
This report describes space charge behavior of polyethylene (PE) grafted with acrylic monomers such as acrylic acid (AA), methacrylate (MA), ethylacrylate (EA) and n-butyl acrylate (NBA). The specimens were 0.7 mm thick with semicon electrodes, and vacuum degassed. Heterocharge is found in ungrafted control PE. This heterocharge decreases with the increase of AA content when AA is grafted onto the PE chains. This was attributed to an enhanced charge trapping at carbonyl sites provided by AA. When other acrylic monomers are grafted, heterocharge of the control PE increases first at low graft ratios and then decreases at higher graft ratios. This change was attributed to the combined effects of alkoxy groups acting as electron donating species and carbonyls acting as charge trapping sites. It seems that charge trapping at the carbonyls is sacrificed in part by the alkoxy groups at low graft ratios. All grafted polyethylenes are found at low fields below 1×105 V/cm to obey the space-charge limited conduction (SCLC) mechanism. Effective charge mobilities of PE-g-AA and PE-g-NBA decrease with the increase of graft ratio while those of others remain unchanged 相似文献
993.
Kwonju Yi Changkyu Choi Sungjoo Suh ByungIn Yoo Jae‐Joon Han Dusik Park Changyeong Kim 《Journal of the Society for Information Display》2011,19(1):48-56
Abstract— In this paper, a novel multi‐touch LCD architecture with hover‐sensing capability is described. To detect multiple touch points and hover points simultaneously, a sensitive backlight, which is a backlight integrated with an IR sensor array, is introduced. The sensitive backlight uses visible light to display contents on a display screen and is also used to detect reflected IR light from objects on or near the display screen. The captured image from the sensitive backlight is used to extract touch and hover information. The proposed display architecture maintains the slim form factor of an LCD with no loss of display quality, while making it possible to sense multiple touches and hovers simultaneously. 相似文献
994.
Knowledge management involves the systematic management of vital knowledge resources and the associated processes of creating, gathering, organizing, diffusion, utilizing and exploiting information. A key challenge emerging for organizations is how to encourage knowledge sharing within an organization because knowledge is an organization’s intellectual capital and is of increasing importance in gaining a competitive business advantage. Isolated initiatives for promoting knowledge sharing and team collaboration without taking into consideration the limitations and constraints of knowledge sharing can halt any further development in the KM culture of an operation. This article investigates knowledge sharing bottlenecks and proposes the use of conversational knowledge sharing as an effective instrument for knowledge sharing. And to develop strategies, this paper determines the causes and effects of knowledge barriers and proposes solutions by using HOQ. The article introduces a financial company case study as a best practice example of conversational knowledge sharing. Then, the paper analyzes the case study to provide evidence for the feasibility and effectiveness of the proposed approach. 相似文献
995.
An analytic solution to Lyapunov functional equations for distributed delay systems is derived. The analytic solution is computed using a matrix exponential function, while conventional computation has been relied on numerical approximations. Based on the analytic solution, a necessary and sufficient stability condition for distributed delay systems with unknown but bounded constant delay is proposed. 相似文献
996.
Scanning electron microscopy and energy dispersive X-ray analyses were carried out in a comparative investigation of Pb(2+) accumulation in Saccharomyces cerevisiae and Aureobasidium pullulans. In S. cerevisiae, the time required to reach an equilibrium state was shortened from 100 h to 1 h as the initial Pb(2+) concentration decreased from 96.5 mg/l to 16.0 mg/l, whereas the time was almost independent of initial Pb(2+) concentration in A. pullulans. Concomitant with the Pb(2+) accumulation, the cell surface of S. cerevisiae became rough and the amounts of potassium, phosphorus and sulfur on the cell surface decreased. However, significant increase of Pb(2+) on the cell surface after Pb(2+) accumulation was not observed due to Pb(2+) penetration into the cell interior. In contrast, the Pb(2+) accumulation had no significant effect on the surface characteristics of A. pullulans and extreme Pb(2+) accumulation was observed on the cell surface because Pb(2+) could not penetrate into the cell interior due to the existence of extracellular polymeric substances. 相似文献
997.
To elevate the Cyclo-His-Pro (CHP) content in yeast, the yeast hydrolysate that was obtained from enzymatic hydrolysis was subjected to various treatments. Flavourzyme-treated hydrolysate showed the highest CHP content (674.0 μg/g) among the various proteases treatments. Ultrafiltration was selected as the best method for concentrating CHP in yeast hydrolysate, based on the yields and CHP contents. In addition, we evaluated the radical scavenge and glucose tolerance of yeast hydrolysate with a high content of CHP. Yeast hydrolysate showed intense scavenging abilities of both 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals. The IC(50) values of yeast hydrolysate on DPPH and ABTS radicals were 1.9 and 0.9 mg/mL, respectively. There were significant differences in glucose level between the diabetes-control and yeast hydrolysate group at 30, 60, 90, and 120 min after injection in a type 1 diabetes model (P < 0.01). Also, there were significant differences in blood glucose levels between the 2 groups at 30, 60, and 100 min after injection in the type 2 diabetes group (P < 0.05). Therefore, it is possible to use the yeast hydrolysate with high levels of CHP as an antioxidative and/or antidiabetic material for the preparation of functional foods. PRACTICAL APPLICATION: This study tried to develop a material containing a high content of CHP using yeast for possible applications of this cyclic dipeptide in the therapy of metabolic disorders. The yeast hydrolysate prepared with Flavourzyme showed a high level of CHP. The hydrolysate with a high content of CHP showed high levels of radical scavenging activities and oral glucose tolerance activity. Therefore, it is possible to use the yeast hydrolysate with high levels of CHP as an antioxidative and/or antidiabetic material for the preparation of functional foods. 相似文献
998.
Jawich D Lteif R Pfohl-Leszkowicz A Strehaiano P 《Molecular nutrition & food research》2006,50(6):552-556
The aim of this study consisted to evaluate the impact of a pesticide (penconazole) on the growth kinetics and genotoxicity on two yeast strains (Saccharomyces cerevisiae and Metschnikowia pulcherrima). When the penconazole was added at different phases of the growth of M. pulcherrima, no effect was noticed on the kinetics of yeast growth but DNA adducts were observed when penconazole was added in the exponential phase. Increasing doses (1-15 maximum residue limit) of the pesticide added at the beginning of the fermentation did not induce DNA adducts while kinetics were affected. 相似文献
999.
Faucet-Marquis V Pont F Størmer FC Rizk T Castegnaro M Pfohl-Leszkowicz A 《Molecular nutrition & food research》2006,50(6):530-542
Ochratoxin A (OTA), a nephrotoxic mycotoxin probably implicated in human Balkan endemic nephropathy and associated urothelial tumors, induces renal carcinomas in rodents and nephrotoxicity in pigs. OTA induces DNA-adduct formation, but the structure of the adducts and their role in nephrotoxicity and carcinogenicity have only partly been elucidated. In vivo, 2-mercaptoethane sulfonate (MESNA) protects rats against OTA-induced nephrotoxicity but not against carcinogenicity, indicating two different mechanisms leading to nephrotoxicity or carcinogenicity. To better understand how DNA-adduct could be generated, opossum kidney cells (OK) have been treated by OTA alone or in presence of several compounds such as MESNA or N-acetylcysteine (another agent that, like MESNA, reduces oxidative stress by increasing of free thiols in kidney), buthionine sulfoximine (BSO) (an inhibitor of glutathione-synthase), and alpha amino-3-chloro-4,5-dihydro-5-isoxazole acetic acid (ACIVICIN) (an inhibitor of gamma glutamyl transpeptidase). Cytotoxicity of OTA on OK cells was evaluated by applying the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. None of the listed agents diminished OTA cytotoxicity significantly; ACIVICIN even increases OTA cytotoxicity. In contrast, analysis of the HPLC profiles of OTA metabolites produced during these incubations indicated that the pattern, the quantity of metabolites, and the nature of the derivatives were modulated by these agents. Ochratoxin B (OTB), open-ring ochratoxin A (OP-OA), 4 hydroxylated OTA, 10 hydroxylated OTA, OTA without phenylalanine, OTB without phenylalanine, and a dechlorinated OTA metabolite could be identified by nano-ESI-IT-MS. 相似文献
1000.