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191.
Dry matter is increasingly recognised as a reliable indicator of fruit quality and consumer acceptance for numerous commodities. To establish dry matter as an at-harvest metric predictive of post-storage and ripening consumer acceptance in pear, cv. d'Anjou fruits were segregated into low (<13%), moderate (13–15.99%) and high (≥16%) predicted dry matter classifications at harvest using near-infrared spectroscopy and evaluated by untrained consumer panels following cold storage and ripening. Consumers significantly favoured higher dry matter fruits over lower dry matter fruits in terms of perceived firmness, crunchiness, juiciness, sweetness, flavour and overall liking. Consumers were willing to pay premium prices for higher dry matter fruits at an estimated $0.20/lb above average retail prices. Sorting fruit by dry matter at harvest via near-infrared spectroscopy may overcome issues of variation in fruit maturity and quality to produce more consistent consumer experiences in pears following post-storage ripening.  相似文献   
192.
Azobenzene‐containing poly(amic acid)s and resulting polyimides were synthesized. Polymers differed in the polymer backbone structure and the position at which the azobenzene group was attached to the polymer chain. Polymers were characterized and evaluated using Fourier transform infrared, 1H NMR and UV‐visible spectroscopies, X‐ray diffraction, differential scanning calorimetry (DSC) and thermogravimetric analysis. Polyimides revealed glass transition temperatures in the range 160–265 °C, and thermal stability with decomposition temperatures in the range 336–444 °C. The thermal imidization kinetics of poly(amic acid)s was investigated by means of DSC. Kinetic parameters, such as the activation energy (E) and the frequency factor, were estimated using the Ozawa and Kissinger models. The values of E, determined using both methods, were in the range 142.52–200.92 kJ mol?1. The photoinduced optical anisotropy (POA) was studied in the obtained azopolymers using a holographic grating recording technique. Surface relief gratings, which appeared after light exposure, were observed using atomic force microscopy. For the first time to the best of our knowledge, photoinduced anisotropy in poly(amic acid)s was studied and compared with POA in their polyimide analogues. © 2014 Society of Chemical Industry  相似文献   
193.
End-stage kidney disease (ESKD) is a main public health problem, the prevalence of which is continuously increasing worldwide. Due to adverse effects of renal replacement therapies, kidney transplantation seems to be the optimal form of therapy with significantly improved survival, quality of life and diminished overall costs compared with dialysis. However, post-transplant patients frequently suffer from post-transplant diabetes mellitus (PTDM) which an important risk factor for cardiovascular and cardiovascular-related deaths after transplantation. The management of post-transplant diabetes resembles that of diabetes in the general population as it is based on strict glycemic control as well as screening and treatment of common complications. Lifestyle interventions accompanied by the tailoring of immunosuppressive regimen may be of key importance to mitigate PTDM-associated complications in kidney transplant patients. More transplant-specific approach can include the exchange of tacrolimus with an alternative immunosuppressant (cyclosporine or mammalian target of rapamycin (mTOR) inhibitor), the decrease or cessation of corticosteroid therapy and caution in the prescribing of diuretics since they are independently connected with post-transplant diabetes. Early identification of high-risk patients for cardiovascular diseases enables timely introduction of appropriate therapeutic strategy and results in higher survival rates for patients with a transplanted kidney.  相似文献   
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195.
The O-H...N and O-H...O hydrogen bonds were investigated in 10-hydroxybenzo[h]quinoline (HBQ) and benzo[h]quinoline-2-methylresorcinol complex in vacuo, solvent and crystalline phases. The chosen systems contain analogous donor and acceptor moieties but differently coupled (intra- versus intermolecularly). Car–Parrinello molecular dynamics (CPMD) was employed to shed light onto principle components of interactions responsible for the self-assembly. It was applied to study the dynamics of the hydrogen bonds and vibrational features as well as to provide initial geometries for incorporation of quantum effects and electronic structure studies. The vibrational features were revealed using Fourier transformation of the autocorrelation function of atomic velocity and by inclusion of nuclear quantum effects on the O-H stretching solving vibrational Schrödinger equation a posteriori. The potential of mean force (Pmf) was computed for the whole trajectory to derive the probability density distribution and for the O-H stretching mode from the proton vibrational eigenfunctions and eigenvalues incorporating statistical sampling and nuclear quantum effects. The electronic structure changes of the benzo[h]quinoline-2-methylresorcinol dimer and trimers were studied based on Constrained Density Functional Theory (CDFT) whereas the Electron Localization Function (ELF) method was applied for all systems. It was found that the bridged proton is localized on the donor side in both investigated systems in vacuo. The crystalline phase simulations indicated bridged proton-sharing and transfer events in HBQ. These effects are even more pronounced when nuclear quantization is taken into account, and the quantized Pmf allows the proton to sample the acceptor area more efficiently. The CDFT indicated the charge depletion at the bridged proton for the analyzed dimer and trimers in solvent. The ELF analysis showed the presence of the isolated proton (a signature of the strongest hydrogen bonds) only in some parts of the HBQ crystal simulation. The collected data underline the importance of the intramolecular coupling between the donor and acceptor moieties.  相似文献   
196.
描述了德国立达(Rieter)公司提出的应用于RSB-D 35的CUBIcan线上的矩形条筒新概念。介绍了这一新概念,内容包括:与传统的条筒相比,用于并条和随后的纺纱工序时其技术和经济方面的优势,通过优化升降装置的下降运动,可能带来的条筒容条量的增加。将来,这将有助于纺纱厂生产纱线时有效地利用条筒。  相似文献   
197.
It is predicted that the catalytic decomposition of methane (CDM) can be a promising pro-ecological method of hydrogen production. The main drawback of this process is fast deactivation of the catalyst by the carbonaceous deposit formed on its surface. This problem can be effectively solved e.g. by methane decomposition in the presence of ethylene. However, as ethylene is expensive, an attempt was made to synthesise it in situ, in the process of oxidative coupling of methane (OCM), which was subsequently combined with the CDM process in one reactor. As OCM catalysts the sodium–calcium or lithium–magnesium oxide systems were tested, while the CDM catalyst was activated carbon. The optimum conditions of ethylene production were established and applied to conduct the combined OCM–CDM process. The combined process was found to produce hydrogen in higher yields than when only the activated carbon catalyst was used. This observation was explained by formation of catalytically active carbonaceous deposit appearing as a result of decomposition of ethylene.  相似文献   
198.
The objective of this study was to determine if Chardonnay grape seed pomace (GSP), a waste stream of wine production, could be used as a functional ingredient in brewed coffee. Two consumer panels were conducted to assess the acceptance of coffee at coffee replacement (w/w) values of 0% (control), 6.25%, 12.50%, 18.75%, or 25% GSP. The 1st consumer panel (n = 80) assessed the coffee samples served “black.” The 2nd panel (n = 67) assessed the coffee samples with adjustment (that is, sweeteners, milk, and cream) options available. Consumer sensory evaluation involved evaluating the 5 treatments individually for acceptance of appearance, aroma, taste/flavor, and overall acceptance using a 9‐point hedonic scale. A check‐all‐that‐apply questionnaire surveyed the sensory attributes describing aroma, appearance, and taste/flavor of the samples. Oxygen radical absorbance capacity was used to measure the effects of antioxidant levels in GSP coffee samples. Results showed that GSP could be added at 6.25% replacement without significantly affecting the overall consumer acceptance of coffee compared to the control (0% GSP). Above 6.25% GSP supplementation, the coffee beverage was described as more tan, milky, watery/dilute, and mild, and was generally less accepted by the consumers. GSP also increased the antioxidant capacity of the coffee compared to the control (0% GSP), with no significant differences among replacement values. Therefore, 6.25% GSP replacement is recommended for creating coffee beverages acceptable to consumers. Further in vivo investigation may substantiate the free‐radical scavenging capacity of GSP coffee and its potential health benefits.  相似文献   
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200.
Ischemic stroke is the third leading cause of death in the world, which accounts for almost 12% of the total deaths worldwide. Despite decades of research, the available and effective pharmacotherapy is limited. Some evidence underlines the beneficial properties of hydrogen sulfide (H2S) donors, such as NaSH, in an animal model of brain ischemia and in in vitro research; however, these data are ambiguous. This study was undertaken to verify the neuroprotective activity of AP39, a slow-releasing mitochondria-targeted H2S delivery molecule. We administered AP39 for 7 days prior to ischemia onset, and the potential to induce brain tolerance to ischemia was verified. To do this, we used the rat model of 90-min middle cerebral artery occlusion (MCAO) and used LC-MS/MS, RT-PCR, LuminexTM assays, Western blot and immunofluorescent double-staining to determine the absolute H2S levels, inflammatory markers, neurotrophic factor signaling pathways and apoptosis marker in the ipsilateral frontal cortex, hippocampus and in the dorsal striatum 24 h after ischemia onset. AP39 (50 nmol/kg) reduced the infarct volume, neurological deficit and reduced the microglia marker (Iba1) expression. AP39 also exerted prominent anti-inflammatory activity in reducing the release of Il-1β, Il-6 and TNFα in brain areas particularly affected by ischemia. Furthermore, AP39 enhanced the pro-survival pathways of neurotrophic factors BDNF-TrkB and NGF-TrkA and reduced the proapoptotic proNGF-p75NTR-sortilin pathway activity. These changes corresponded with reduced levels of cleaved caspase 3. Altogether, AP39 treatment induced adaptative changes within the brain and, by that, developed brain tolerance to ischemia.  相似文献   
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