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101.
Elina 《影像视觉》2011,(7):116-127
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102.
In this paper, private gardens are portrayed as spaces and implements of aristocratic passion for plant collecting, of competition within the gentry, as well as of scientific professionalisation for botanists. This paper traces the early history of botanical collections in the Russian Empire from the 18th to the early 19th century as part of an elite culture which encouraged amateur patrons to invest in expeditions, gardens, and, consequently, in professionals to manage such projects. Young graduates of European universities who began their careers working at private botanical institutions could later successfully apply for academic positions. The circulation of specimens had developed as a key element of botanical collection and an important basis for the networking of professionals and amateurs around the world. This paper argues that collecting plant specimens became an important means for engaging in “power games” and even “plant diplomacy.” These new responsibilities significantly increased botanists' status as experts. A diverse group of personalities, such as the Empress Catherine II, King George III of England, the industrialist Prokophy Demidov, aristocrat Alexei Razumovsky, Joseph Banks, President of the Royal Society, the academician Peter Simon Pallas—all shared a passion for botanical collecting and were engaged in power games at different levels, using botany as an instrument of influence.  相似文献   
103.
A growing number of consumers opt for plant-based milk substitutes for medical reasons or as a lifestyle choice. Medical reasons include lactose intolerance, with a worldwide prevalence of 75%, and cow's milk allergy. Also, in countries where mammal milk is scarce and expensive, plant milk substitutes serve as a more affordable option. However, many of these products have sensory characteristics objectionable to the mainstream western palate. Technologically, plant milk substitutes are suspensions of dissolved and disintegrated plant material in water, resembling cow's milk in appearance. They are manufactured by extracting the plant material in water, separating the liquid, and formulating the final product. Homogenization and thermal treatments are necessary to improve the suspension and microbial stabilities of commercial products that can be consumed as such or be further processed into fermented dairy-type products. The nutritional properties depend on the plant source, processing, and fortification. As some products have extremely low protein and calcium contents, consumer awareness is important when plant milk substitutes are used to replace cow's milk in the diet, e.g. in the case of dairy intolerances. If formulated into palatable and nutritionally adequate products, plant-based substitutes can offer a sustainable alternative to dairy products.  相似文献   
104.
Potato puree and penne pasta were inoculated with cereulide producing B. cereus 5964a and B. cereus NS117. Static incubation at 28 degrees C proved these two foods to be a better substrate for higher cereulide production (4,080 ng/g in puree and 3,200 ng/g in penne were produced by B. cereus 5964a during 48 h of incubation) compared with boiled rice (2,000 ng/g). This difference occurred despite B. cereus counts of more than 10(8) CFU/g in all three products. Aeration of cultures had a negative effect on cereulide production, causing concentrations more than 10-fold lower than in some statically incubated samples. Cereulide production remained undetectable in shaken milk, whereas it reached 1,140 ng/ml in statically incubated milk. At 12 and 22 degrees C, presence of background flora was also a determinative factor. A total B. cereus count of more than 106 CFU/ml did not necessarily lead to uniform cereulide production and was also dependent on the B. cereus strain involved. In this study, we confirm that a number of factors play a crucial role in the determination of the extent to which, if at all, cereulide will be produced. Among those, type of the food, temperature, pH, and whether additional aeration (via incubation on an orbital shaker) is induced had an important role. An important effect was also induced by the cereulide-producing strain involved.  相似文献   
105.
The nucleus accumbens core (NAcc) is an important component of brain reward circuitry, but studies have revealed its involvement in pain circuitry also. However, its effect on trigeminal neuralgia (TN) and the mechanism underlying it are yet to be fully understood. Therefore, this study aimed to examine the outcomes of optogenetic stimulation of NAcc GABAergic neurons in an animal model of TN. Animals were allocated into TN, sham, and control groups. TN was generated by infraorbital nerve constriction and the optogenetic virus was injected into the NAcc. In vivo extracellular recordings were acquired from the ventral posteromedial nucleus of the thalamus. Alterations of behavioral responses during stimulation “ON” and “OFF” conditions were evaluated. In vivo microdialysis was performed in the NAcc of TN and sham animals. During optogenetic stimulation, electrophysiological recordings revealed a reduction of both tonic and burst firing activity in TN animals, and significantly improved behavioral responses were observed as well. Microdialysis coupled with liquid chromatography/tandem mass spectrometry analysis revealed significant alterations in extracellular concentration levels of GABA, glutamate, acetylcholine, dopamine, and citrulline in NAcc upon optic stimulation. In fine, our results suggested that NAcc stimulation could modulate the transmission of trigeminal pain signals in the TN animal model.  相似文献   
106.
Microbial risk assessment provides a means of estimating consumer risks associated with food products. The methods can also be applied at the plant level. In this study results of microbiological analyses were used to develop a robust single plant level risk assessment. Furthermore, the prevalence and numbers of Listeria monocytogenes in marinated broiler legs in Finland were estimated. These estimates were based on information on the prevalence, numbers and genotypes of L. monocytogenes in 186 marinated broiler legs from 41 retail stores. The products were from three main Finnish producers, which produce 90% of all marinated broiler legs sold in Finland. The prevalence and numbers of L. monocytogenes were estimated by Monte Carlo simulation using WinBUGS, but the model is applicable to any software featuring standard probability distributions. The estimated mean annual number of L. monocytogenes-positive broiler legs sold in Finland was 7.2x10(6) with a 95% credible interval (CI) 6.7x10(6)-7.7x10(6). That would be 34%+/-1% of the marinated broiler legs sold in Finland. The mean number of L. monocytogenes in marinated broiler legs estimated at the sell-by-date was 2 CFU/g, with a 95% CI of 0-14 CFU/g. Producer-specific L. monocytogenes strains were recovered from the products throughout the year, which emphasizes the importance of characterizing the isolates and identifying strains that may cause problems as part of risk assessment studies. As the levels of L. monocytogenes were low, the risk of acquiring listeriosis from these products proved to be insignificant. Consequently there was no need for a thorough national level risk assessment. However, an approach using worst-case and average point estimates was applied to produce an example of single producer level risk assessment based on limited data. This assessment also indicated that the risk from these products was low. The risk-based approach presented in this work can provide estimation of public health risk on which control measures at the plant level can be based.  相似文献   
107.
Interpretations of ambiguous sentences were studied in patients with unilateral anterior temporal lobectomy or selective amygdalo-hippocampectomy. The sentences represented lexical and syntactic ambiguities. In both left- and right-sided groups, regardless of type of surgery, total mean score on the test was below normal. Left-sided cases, regardless of type of surgery, provided significantly fewer alternative interpretations than right-sided cases. The results suggest greater left than right hemisphere specialization in both lexical and syntactic processing, but also suggest right hemisphere involvement in resolution of lexical ambiguity.  相似文献   
108.
In this paper, we study multidisciplinary optimization problems where the objective functions and the vector-valued mathematical models are not necessarily differentiable in a classical sense. Moreover, we assume that the state equation consists of several submodels, that is, unit-process models. This study is based on the nonsmooth analysis introduced by Clarke and the theory of H-differentiable functions by Gowda. It concentrates on two mathematical tools needed in sensitivity analysis of the multidisciplinary optimization problems, namely, the generalized chain rule for vector-valued functions and the implicit subdifferentiation formula. We employ these tools to obtain subgradient information of the problems considered. Finally, we present a numerical example and compare the obtained results with finite differences by means of accuracy and computational efficiency.  相似文献   
109.
Blends of microcrystalline chitosan (MCCh) with cellulose xhanthate alkaline solutions were prepared to investigate the effects of aqueous MCCh gel concentration and additives on the spinnability of hybrid cellulose/chitosan fibers and their properties. The properties of the spinning solution were mainly dependent on the concentration of MCCh in the aqueous gel‐like dispersion and the amount mixed into the cellulose xhanthate solution. Sodium alginate chemically close to cellulose and chitosan was used as an additive to improve the miscibility of chitosan due to the ionic bonds formed with chitosan 2‐amino groups. Using an optimized ratio of 2 : 1 of MCCh to the sodium alginate, a maximum of 6% of MCCh calculated from alpha‐cellulose content could be introduced into the sodium xhanthate solution containing originally 9% of alpha‐cellulose. The yield of MCCh in the resulting fibers was dependent on the molecular mass, and varied between 73–82%. The strength, elongation, and color of the resulting hybrid fibers were only slightly changed and the WRV remarkably increased compared to standard fibers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1725–1730, 2000  相似文献   
110.
In the present study, we examined the bone healing capacity of Meox2, a homeobox gene that plays essential roles in the differentiation of a range of developing tissues, and identified its putative function in palatogenesis. We applied the knocking down of Meox2 in human periodontal ligament fibroblasts to examine the osteogenic potential of Meox2. Additionally, we applied in vivo periodontitis induced experiment to reveal the possible application of Meox2 knockdown for 1 and 2 weeks in bone healing processes. We examined the detailed histomorphological changes using Masson’s trichrome staining and micro-computed tomography evaluation. Moreover, we observed the localization patterns of various signaling molecules, including α-SMA, CK14, IL-1β, and MPO to examine the altered bone healing processes. Furthermore, we investigated the process of bone formation using immunohistochemistry of Osteocalcin and Runx2. On the basis of the results, we suggest that the knocking down of Meox2 via the activation of osteoblast and modulation of inflammation would be a plausible answer for bone regeneration as a gene therapy. Additionally, we propose that the purpose-dependent selection and application of developmental regulation genes are important for the functional regeneration of specific tissues and organs, where the pathological condition of tooth loss lesion would be.  相似文献   
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