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91.
Etienne Urbah Peter Kacsuk Zoltan Farkas Gilles Fedak Gabor Kecskemeti Oleg Lodygensky Attila Marosi Zoltan Balaton Gabriel Caillat Gabor Gombas Adam Kornafeld Jozsef Kovacs Haiwu He Robert Lovas 《Journal of Grid Computing》2009,7(3):335-354
Desktop Grids, such as XtremWeb and BOINC, and Service Grids, such as EGEE, are two different approaches for science communities to gather computing power from a large number of computing resources. Nevertheless, little work has been done to combine these two Grid technologies in order to establish a seamless and vast Grid resource pool. In this paper we present the EGEE Service Grid, the BOINC and XtremWeb Desktop Grids. Then, we present the EDGeS solution to bridge the EGEE Service Grid with the BOINC and XtremWeb Desktop Grids. 相似文献
92.
Klein Daniel N.; Santiago Neil J.; Vivian Dina; Blalock Janice A.; Kocsis James H.; Markowitz John C.; McCullough James P. Jr.; Rush A. John; Trivedi Madhukar H.; Arnow Bruce A.; Dunner David L.; Manber Rachel; Rothbaum Barbara; Thase Michael E.; Keitner Gabor I.; Miller Ivan W.; Keller Martin B. 《Canadian Metallurgical Quarterly》2004,72(4):681
Although the efficacy of maintenance pharmacotherapy for the prevention of recurrence in major depressive disorder (MDD) is well documented, few studies have tested the efficacy of psychotherapy as a maintenance treatment. The authors examined the efficacy of the cognitive-behavioral analysis system of psychotherapy (CBASP) as a maintenance treatment for chronic forms of MDD. Eighty-two patients who had responded to acute and continuation phase CBASP were randomized to monthly CBASP or assessment only for 1 year. Significantly fewer patients in the CBASP than assessment only condition experienced a recurrence. The 2 conditions also differed significantly on change in depressive symptoms over time. These findings support the use of CBASP as a maintenance treatment for chronic forms of MDD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Shruthi Thada Gabor L. Horvath Mario M. Müller Nickel Dittrich Melanie L. Conrad Saubashya Sur Abid Hussain Karin Pelka Suman Latha Gaddam Eicke Latz Hortense Slevogt Ralf R. Schumann Sanne Burkert 《International journal of molecular sciences》2021,22(4)
The interaction and crosstalk of Toll-like receptors (TLRs) is an established pathway in which the innate immune system recognises and fights pathogens. In a single nucleotide polymorphisms (SNP) analysis of an Indian cohort, we found evidence for both TLR4-399T and TRL8-1A conveying increased susceptibility towards tuberculosis (TB) in an interdependent manner, even though there is no established TLR4 ligand present in Mycobacterium tuberculosis (Mtb), which is the causative pathogen of TB. Docking studies revealed that TLR4 and TLR8 can build a heterodimer, allowing interaction with TLR8 ligands. The conformational change of TLR4-399T might impair this interaction. With immunoprecipitation and mass spectrometry, we precipitated TLR4 with TLR8-targeted antibodies, indicating heterodimerisation. Confocal microscopy confirmed a high co-localisation frequency of TLR4 and TLR8 that further increased upon TLR8 stimulation. The heterodimerisation of TLR4 and TLR8 led to an induction of IL12p40, NF-κB, and IRF3. TLR4-399T in interaction with TLR8 induced an increased NF-κB response as compared to TLR4-399C, which was potentially caused by an alteration of subsequent immunological pathways involving type I IFNs. In summary, we present evidence that the heterodimerisation of TLR4 and TLR8 at the endosome is involved in Mtb recognition via TLR8 ligands, such as microbial RNA, which induces a Th1 response. These findings may lead to novel targets for therapeutic interventions and vaccine development regarding TB. 相似文献
94.
Ziegler–Natta heterogeneous catalytic systems are extensively used to polymerize ethylene and propylene. Some industrial catalysts
consist of TiCl4 chemisorbed on activated MgCl2 and subsequently reduced and alkylated by reaction with an aluminum alkyl (generally AlEt3). Lewis bases are added to the catalytic systems to control the enantio-selectivity for the production of isotactic polypropylene.
Our aim is to clarify the chemical composition of the active centers by modern surface science methods. Model catalysts are
prepared in the form of ultra-thin films by gas-phase deposition on a gold foil in ultrahigh vacuum. Under these conditions,
MgCl2 films grow to controlled thickness via a layer-by-layer mechanism, as revealed by AES and XPS. TiCl4 can be deposited on these films near room temperature by both electron irradiation-induced and metallic magnesium-induced
chemical vapor deposition. Angle-resolved XPS studies indicate that these films consist of a few layers of TiCl2 with one monolayer of TiCl4 chemisorbed on its surface. The exposure of these titanium chloride films to the co-catalyst AlEt3 produces an active model Ziegler–Natta catalyst. XPS analysis reveals the presence of TiCl2Et on the catalyst surface: this is believed to be the active site. Prolonged reaction with the co-catalyst reduces the titanium
sites to TiClEtn (n = 1 and/or 2). High molecular weight polyethylene and polypropylene are synthesized on these catalysts, as shown by Raman
spectroscopy. Highly isotactic polypropylene is produced without need for stereo-regulating Lewis bases.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
95.
Vesper BJ Altman KW Elseth KM Haines GK Pavlova SI Tao L Tarjan G Radosevich JA 《ChemMedChem》2008,3(4):552-559
Gastroesophageal reflux disease (GERD) affects both men and women worldwide, with the most common symptom of GERD being frequent heartburn. If left untreated, more serious diseases including esophagitis and/or esophageal cancer may result. GERD has been commonly held to be the result of gastric acid refluxing into the esophagus. Recent work, however, has shown that there are acid-producing cells in the upper aerodigestive tract. In addition, acid-producing bacteria located within the upper gastrointestinal tract and oral cavity may also be a contributing factor in the onset of GERD. Proton pump inhibitors (PPIs) are commonly prescribed for treating GERD; these drugs are designed to stop the production of gastric acid by shutting down the H(+)/K(+)-ATPase enzyme located in parietal cells. PPI treatment is systemic and therefore significantly different than traditional antacids. Although a popular treatment choice, PPIs exhibit substantial interpatient variability and commonly fail to provide a complete cure to the disease. Recent studies have shown that H(+)/K(+)-ATPases are expressed in tissues outside the stomach, and the effects of PPIs in these nongastric tissues have not been fully explored. Likewise, acid-producing bacteria containing proton pumps are present in both the oral cavity and esophagus, and PPI use may also adversely affect these bacteria. The use of PPI therapy is further complicated by the two philosophical approaches to treating this disease: to treat only symptoms or to treat continuously. The latter approach frequently results in unwanted side effects which may be due to the PPIs acting on nongastric tissues or the microbes which colonize the upper aerodigestive tract. 相似文献
96.
Forty microampere current was generated on a platinum-titanium dioxide Schottky diode during the platinum catalyzed steady-state oxidation of carbon monoxide at 80 degrees C. For reaction events that produced four CO(2) molecules, three injected electrons were collected in a diode comprising a 5 nm thick platinum and a 150 nm titanium dioxide film. The electron injection flux depends on the thickness of the platinum and the titanium dioxide diode properties as well as the conditions of the catalytic reactions. 相似文献
97.
In this contribution, we report the synthesis of rhodium multipods that result from a homogeneous seeded growth mechanism. Small Rh nanocrystal seeds were synthesized by the reduction of RhCl3 in ethylene glycol in the presence of PVP. These seed particles could be subsequently used, without isolation, to form larger rhodium nanoparticles. A reaction temperature of 190 degrees C led to isotropic cubic Rh particles. Lowering the reaction temperature resulted in more anisotropic growth, which gave Rh cubes with horns at 140 degrees C, and Rh multipods at 90 degrees C. The anisotropic growth occurred in the (111) direction, as determined by high-resolution TEM (HRTEM). Anisotropic growth proceeds via a seeded growth mechanism, and not by oriented attachment. 相似文献
98.
Abdominal exercises are widely used to develop the anterior muscles of the trunk. These exercises can be undertaken without the aid of equipment, but increasingly manufacturers are developing equipment which purportedly enhances the training effect for abdominal muscles. As there are many different products and exercises used for abdominal muscle development, it is likely that some are more effective than others. This study aimed to investigate the effectiveness of five commonly performed abdominal exercises. A second aim was to investigate the effects of fatigue on these exercises. Five different types of abdominal exercise [standard crunch (sit-up) with bent knees, gym ball crunch, crunch with 5 kg weight held behind the head, legs raised crunch and a commercially manufactured roller crunch] were examined using integrated surface electromyography (IEMG). The lower rectus abdominis (LRA), upper rectus abdominis (URA) and obliquus externus abdominis (EO) of 15 healthy male participants [age (mean +/- SD) 22.2 +/- 6.8 years; height 1.77 +/- 0.06 m; mass 79.3 +/- 10.7 kg] were monitored using a four-channel special purpose EMG data logger. Three trials of each exercise were performed in random order and normalized to enable comparisons between muscles and exercises. At a later date, ten participants were then re-tested when fresh and after a 30 min whole-body fatigue protocol that specifically targeted the abdominal muscles. Two exercises were evaluated, the abdominal roller crunch and legs raised crunch, which were judged to be the least and most effective, respectively, of the five exercises previously used. The normalized IEMG showed significant (p < 0.001) differences between exercises (gym ball crunch = 86.0 +/- 7.5%; legs raised crunch = 79.9 +/- 5.1%; 5 kg weight crunch = 65.1 +/- 13.4%; standard crunch = 56.2 +/- 3.2%; and roller crunch = 45.0 +/- 11.4%). Post-fatigue, the normalized mean IEMG for both exercises increased significantly (p < 0.05) for LRA and URA muscles but not for the EO (p > 0.05). It was concluded that exercises can be constructed to provide a greater challenge to abdominal muscles, commercially available roller-type equipment appears to be little different from the standard abdominal crunch with bent knees, and fatiguing exercise results in the LRA and URA being more highly activated. These findings provide more detailed knowledge and understanding of the effects of different forms of abdominal exercise. 相似文献
99.
The compositions of lipid classes as well as the molecular species composition of subclasses (diacyl, alkylacyl, and alkenylacyl
forms) of choline and ethanolamine phosphoglycerides in marine amphipod crustaceans, Gammarus spp., collected in the Baltic Sea at 8 and 15°C, were studied in relation to environmental temperature. The structural order
of phospholipid multibilayers was also determined. Environmental temperature had little effect on fatty acid composition.
The level of some polyunsaturated fatty acids, such as 20:4, even increased in choline and ethanolamine phosphoglycerides
at 15°C. Ethanolamine phosphoglycerides were rich in alkenylacyl forms, especially in crustaceans collected at 15°C. The accumulation
of sn-1 monoenic, sn-2 polyenic diacyl, alkyl, and alkenylacyl phosphatidylethanolamines and diacyl phosphatidylcholines was observed at 8°C.
The phospholipid vesicles of crustaceans collected at 8°C were more disordered than expected compared to those obtained from
animals collected at 15°C. It was concluded that, in addition to variations in the levels of sn-1 monoenic and sn-2 polyenic phospholipid molecular species with temperature, ethanolamine plasmalogens may play a role in controlling membrane
biophysical properties in marine amphipod crustaceans. 相似文献
100.
Bill S. Hansson Gabor Szöcs Frank Schmidt Wittko Francke Christer Löfstedt Miklos Tóth 《Journal of chemical ecology》1990,16(6):1887-1897
(Z,Z,Z)-3,6,9-nonadecatriene (Z3,Z6,Z9–19Hy) and (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3,Z9-cis-6,7-epo-19Hy) were identified in pheromone gland extracts from femaleErannis defoliaria. The two components were found in a 13 ratio, with the main component,Z3,Z9-cis-6,7-epo-19Hy present at an amount of about 1.5 ng per female. The components were identified by means of gas chromatography-mass spectrometry, gas chromatography-electroantennography and gas chromatography-single sensillum recordings. Single sensillum measurements on the male antenna showed two physiological types of sensilla. One type was characterized by a large spike amplitude cell responding toZ3,Z9-cis-6,7-epoxy-19Hy and a small spike amplitude cell responding toZ3,Z6,Z9–19Hy. A second type responded only with a large spike amplitude cell to the epoxide, and this cell was inhibited by the triene. Of the two pheromone components, the epoxide gave the higher response in the EAG tests. Preliminary field tests support the identification of the pheromone components. The epoxide was also found to be present in the extract of the pheromone gland ofColotois pennaria, and males ofC. pennaria andAgriopis marginaria were trapped by the mixture of the identified compounds. 相似文献