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991.
The cover image is based on the Research Article Anisotropy in nanocellular polymers promoted by the addition of needle‐like sepiolites by Victoria Bernardo et al. DOI: 10.1002/pi.5813 .

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992.
New experimental study of heavy ion and proton induced SEU at reduced voltage (i.e. reduced critical charge) reveals interesting results. It is shown that the heavy ion cross section and microprobe mapping scale like the threshold LET and the parameter, which is almost invariant under bias changes, is the effective charge collection depth. For studying proton induced SEU and surface-barrier-detector spectra we use protons with energies from 5.6 to 300 MeV. The results are analyzed in view of the processes involved in low energy deposition by protons. Detailed calculations show the importance of straggling in proton direct ionization which might be the leading process in very sensitive devices like photodiodes  相似文献   
993.
Passive polyethylene (PE) samplers were deployed at six locations within Narragansett Bay (RI, USA) to determine sources and trends of freely dissolved and gas-phase polycyclic aromatic hydrocarbons (PAHs) from May to November 2006. Freely dissolved aqueous concentrations of PAHs were dominated by fluoranthene, pyrene, and phenanthrene, at concentrations ranging from tens to thousands of pg/L. These were also the dominant PAHs in the gas phase, at hundreds to thousands of pg/m3. All stations mostly followed the same temporal trends, with highest concentrations (up to 7300 pg/L for sum PAHs) during the second of 11 deployments, coinciding with a major rainstorm. Strong correlations of sum PAHs with river flows and wastewater treatment plant discharges highlighted the importance of rainfall in mobilizing PAHs from a combination of runoff and atmospheric washout. PAH concentrations declined through consecutive deployments III to V, which could be explained by an exponential decay due to flushing with cleaner ocean water during tides. The estimated residence time (tres) of the PAH pulse was 24 days, close to an earlier estimate of tres of 26 days for freshwater in the Bay. Air-water exchange gradients indicated net volatilization of most PAHs closest to Providence. Further south in the Bay, gradients had changed to mostly net uptake of the more volatile PAHs, but net volatilization for the less volatile PAHs. Based on characteristic PAH ratios, freely dissolved PAHs at most sites originated from the combustion of fossil fuels; only two sites were at times affected by fuel spill-derived PAHs.  相似文献   
994.
A rare two-dimensional layered inorganic–organic hybrid material, strontium sulfonate Sr[C2H4(SO3)2] was synthesized by hydrothermal reaction of strontium chloride hexahydrate and ethane disulfonic acid at 160 °C. Single-crystal X-ray diffraction was utilized for structural determination. Data showed that the compound, crystallized in the monoclinic system and space group of C2/c. With cell parameters a = 8.3183(7) Å, b = 5.4416(5) Å and c = 14.9784(13) Å. The new material was extensively studied by DRIFT-infrared spectroscopy, thermogravimetric analysis, SEM and powder X-ray diffraction. Results show that the compound is thermally stable.  相似文献   
995.
996.
Neuropathic pain is a form of chronic pain arising from damage of the neural cells that sense, transmit or process sensory information. Given its growing prevalence and common refractoriness to conventional analgesics, the development of new drugs with pain relief effects constitutes a prominent clinical need. In this respect, drugs that reduce activity of sensory neurons by modulating ion channels hold the promise to become effective analgesics. Here, we evaluated the mechanical antinociceptive effect of IQM-PC332, a novel ligand of the multifunctional protein downstream regulatory element antagonist modulator (DREAM) in rats subjected to chronic constriction injury of the sciatic nerve as a model of neuropathic pain. IQM-PC332 administered by intraplantar (0.01–10 µg) or intraperitoneal (0.02–1 µg/kg) injection reduced mechanical sensitivity by ≈100% of the maximum possible effect, with ED50 of 0.27 ± 0.05 µg and 0.09 ± 0.01 µg/kg, respectively. Perforated-patch whole-cell recordings in isolated dorsal root ganglion (DRG) neurons showed that IQM-PC332 (1 and 10 µM) reduced ionic currents through voltage-gated K+ channels responsible for A-type potassium currents, low, T-type, and high voltage-activated Ca2+ channels, and transient receptor potential vanilloid-1 (TRPV1) channels. Furthermore, IQM-PC332 (1 µM) reduced electrically evoked action potentials in DRG neurons from neuropathic animals. It is suggested that by modulating multiple DREAM–ion channel signaling complexes, IQM-PC332 may serve a lead compound of novel multimodal analgesics.  相似文献   
997.
In the past decade, anti-tumour immune responses have been successfully exploited to improve the outcome of patients with different cancers. Significant progress has been made in taking advantage of different types of T cell functions for therapeutic purposes. Despite these achievements, only a subset of patients respond favorably to immunotherapy. Therefore, there is a need of novel approaches to improve the effector functions of immune cells and to recognize the major targets of anti-tumour immunity. A major hallmark of cancer is metabolic rewiring associated with switch of mitochondrial functions. These changes are a consequence of high energy demand and increased macromolecular synthesis in cancer cells. Such adaptations in tumour cells might generate novel targets of tumour therapy, including the generation of neoantigens. Here, we review the most recent advances in research on the immune response to mitochondrial proteins in different cellular conditions.  相似文献   
998.
Angiopoietin-like protein 8 (ANGPTL8) is an hepatokine altered in several metabolic conditions, such as obesity, type 2 diabetes, dyslipidemia and nonalcoholic fatty liver disease (NAFLD). We sought to explore whether ANGPTL8 is involved in NAFLD amelioration after bariatric surgery in experimental models and patients with severe obesity. Plasma ANGPTL8 was measured in 170 individuals before and 6 months after bariatric surgery. Hepatic ANGPTL8 expression was evaluated in liver biopsies of patients with severe obesity undergoing bariatric surgery with available liver pathology analysis (n = 75), as well as in male Wistar rats with diet-induced obesity subjected to sham operation, sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB) (n = 65). The effect of ANGPTL8 on lipogenesis was assessed in human HepG2 hepatocytes under palmitate-induced lipotoxic conditions. Plasma concentrations and hepatic expression of ANGPTL8 were increased in patients with obesity-associated NAFLD in relation to the degree of hepatic steatosis. Sleeve gastrectomy and RYGB improved hepatosteatosis and reduced the hepatic ANGPTL8 expression in the preclinical model of NAFLD. Interestingly, ANGPTL8 inhibited steatosis and expression of lipogenic factors (PPARG2, SREBF1, MOGAT2 and DGAT1) in palmitate-treated human hepatocytes. Together, ANGPTL8 is involved in the resolution of NAFLD after bariatric surgery partially by the inhibition of lipogenesis in steatotic hepatocytes.  相似文献   
999.
The cis‐trans isomerizations undergone by linoleic acid during industrial deodorization and/or physical refining of edible fats were studied in an experimental discontinuous pilot plant of 250 kg using nitrogen as stripping gas in place of steam. For each oil, the expression of the analytical results has been made as molar fraction, which is kinetically equivalent to making an abstraction from the other components in the reaction bulk and assumes they do not take part in the isomerization. The kinetic constants for the formation of the acids C18:2(9c,12t), C18:2(9t,12c) and C18:2(9t,12t) were determined. The equations and values obtained justify that the reaction orders studied are zero (or can be considered zero) for the time taken in an industrial deodorization and/or physical refining of edible fats. The analytical method used is appropriate for direct application of the results in industry.  相似文献   
1000.
Three control algorithms are developed to stabilize an underactuated two-link robot at its unstable inverted position. The well-known linear quadratic regulator is described first. Next, a stabilization control law using partial feedback linearization is developed where the reference trajectories for the linearized degrees of freedom are designed by analyzing the zero dynamics. The linear quadratic regulator and partial feedback linearization control algorithms both assume an exact dynamic model. To deal with modeling inaccuracies, a robust controller using sliding mode concepts is supplied. Numerical simulations are presented. © 1998 John Wiley & Sons, Inc.  相似文献   
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