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101.
Furan is a suspected human carcinogen and reported to be produced by thermal or ultraviolet light (UV-C) treatment of various foods, such as fruit juices and sugar solutions. This study explores the formation of furan during UV-treatment of high fructose corn syrup (HFCS) solution and simulated juices containing it and validates the results with two real juices, apple juice and apple cider. Studies performed on individual components of fruit juices revealed fructose to be the main constituent in fruit juices that is responsible for furan formation during UV-treatment. Furan formation was promoted at acidic pH, yet was suppressed in the presence of ascorbic acid. Furan synthesis is strongly influenced by absorbance of the treated solution, with increasing absorption coefficient leading to reduced furan formation. Formation of furan in fruit juices sweetened with HFCS when subjected to UV-treatment has been firmly established.  相似文献   
102.
李璠 《世界建筑》2010,(12):26-27
<正>这座住宅的主人是一对带有两个孩子的夫妇。主人一家都对其所居住的社区非常感兴趣,希望能够与大家分享自家住宅的外部空间。作为这个微型总体规划3个步骤的第一步,他们希望这栋住宅能够成为邻里儿童的日间看护中心,由此发挥社区中心的作用。住宅用地位于一整列住宅的尽端——这样的位置与委托人的意图完全吻合。它是清晰界定的前庭与后院之间的断裂带;同  相似文献   
103.
To measure the maximum specific growth rate (μmax) and the half saturation coefficient (Ks), a simple respirometric technique was used, where differing volumes of concentrated wastewater were contacted with biomass in a respirometer and the response measured as a change in oxygen uptake rate (ΔOUR). The ΔOUR was then related to the growth rate, and a series of substrate concentration/growth rate relationships determined from which μmax and Ks were calculated. A freeze concentration technique was developed to concentrate the wastewater. The concentration technique did not alter the response of the microorganisms to the wastewater. Maximum specific growth rates (μmax) and half saturation coefficients (Ks) were found to vary between 1.3 and 1.9 d−1 and 1.5 and 3.2 mg l−1, respectively.  相似文献   
104.
Sea lamprey Petromyzon marinus control in the Great Lakes primarily involves application of lampricides to streams where larval production occurs to kill larvae prior to their metamorphosing and entering the lakes as parasites (juveniles). Because lampricides are not 100% effective, larvae that survive treatment may metamorphose before streams are again treated. Larvae that survive treatment have not been widely studied, so their dynamics are not well understood. We tagged and released larvae in six Great Lake tributaries following lampricide treatment and estimated vital demographic rates using multistate tag-recovery models. Model-averaged larval survivals ranged from 56.8 to 57.6%. Model-averaged adult recovery rates, which were the product of juvenile survivals and adult capture probabilities, ranged from 6.8 to 9.3%. Using stochastic simulations, we estimated production of juvenile sea lampreys from a hypothetical population of treatment survivors under different growth conditions based on parameter estimates from this research. For fast-growing populations, juvenile production peaked 2 years after treatment. For slow-growing populations, juvenile production was approximately one-third that of fast-growing populations, with production not peaking until 4 years after treatment. Our results suggest that dynamics (i.e., survival, metamorphosis) of residual larval populations are very similar to those of untreated larval populations. Consequently, residual populations do not necessarily warrant special consideration for the purpose of sea lamprey control and can be ranked for treatment along with other populations. Consecutive lampricide treatments, which are under evaluation by the sea lamprey control program, would be most effective for reducing juvenile production in large, fast-growing populations.  相似文献   
105.
106.
Regardless of the significant improvements in treatment of melanoma, the majority of patients develop resistance whose mechanisms are still not completely understood. Hence, we generated and characterized two melanoma-derived cell lines, primary WM793B and metastatic A375M, with acquired resistance to the RAF inhibitor vemurafenib. The morphology of the resistant primary WM793B melanoma cells showed EMT-like features and exhibited a hybrid phenotype with both epithelial and mesenchymal characteristics. Surprisingly, the vemurafenib-resistant melanoma cells showed a decreased migration ability but also displayed a tendency to collective migration. Signaling pathway analysis revealed the reactivation of MAPK and the activation of the PI3K/AKT pathway depending on the vemurafenib-resistant cell line. The acquired resistance to vemurafenib caused resistance to chemotherapy in primary WM793B melanoma cells. Furthermore, the cell-cycle analysis and altered levels of cell-cycle regulators revealed that resistant cells likely transiently enter into cell cycle arrest at the G0/G1 phase and gain slow-cycling cell features. A decreased level of NME1 and NME2 metastasis suppressor proteins were found in WM793B-resistant primary melanoma, which is possibly the result of vemurafenib-acquired resistance and is one of the causes of increased PI3K/AKT signaling. Further studies are needed to reveal the vemurafenib-dependent negative regulators of NME proteins, their role in PI3K/AKT signaling, and their influence on vemurafenib-resistant melanoma cell characteristics.  相似文献   
107.
108.
The ionic conductivity of Nafion® 1100 extruded membranes re‐cast from solutions of butan‐1‐ol and propan‐2‐ol is measured in 0.5 mol dm–3 H2SO4 at 295 K, using an immersed, four‐electrode d.c. technique. The general trend is an increasing conductivity for the thicker membranes. Materials which were solution‐cast from butan‐1‐ol yielded the highest conductivity while a series of membranes with lower conductivities (similar to those of an extruded Nafion® 1100 series of membranes) was found using propan‐2‐ol. The conductivity results indicate that membranes manufactured by extrusion and casting from various solvents might have different structures. Differences in the water content and conductivity of the membranes are considered to arise from the impact of processing conditions on the surface and bulk structure of the membranes.  相似文献   
109.
Studied the relationship between pregnant women's fantasy representations on the Rorschach test and later attachment status of their 1-yr-olds. The Manual for Assessing Primary Process Manifestations in Rorschach Responses (R. R. Holt, 1968) was used to score Rorschach protocols gathered from 25 women during their 1st pregnancies. Later, the 1-yr-olds and their mothers were videotaped in the Strange Situation to assess infant attachment behaviors. Findings support the hypothesis that primary process integration during pregnancy is significantly and positively related to infant security of attachment. Results also suggest a relation between empathic maternal behaviors and dimensions of mothers' unconscious mental representations measurable prior to the infant's birth. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
A series of cation exchange membranes was produced by impregnating and coating both sides of a quartz web with a Nafion® solution (1100 EW, 10%wt in water). Inert filler particles (SiO2, ZrO2 or TiO2; 5-20%wt) were incorporated into the aqueous Nafion® solution to produce robust, composite membranes. Ion-exchange capacity/equivalent weight, water take-up, thickness change on hydration and ionic and electrical conductivity were measured in 1 mol dm−3 sulfuric acid at 298 K. The TiO2 filler significantly impacted on these properties, producing higher water take-up and increased conductivity. Such membranes may be beneficial for proton exchange membrane (PEM) fuel cell operation at low humidification. The PEM fuel cell performance of the composite membranes containing SiO2 fillers was examined in a Ballard Mark 5E unit cell. While the use of composite membranes offers a cost reduction, the unit cell performance was reduced, in practice, due to drying of the ionomer at the cathode.  相似文献   
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