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151.
Quartz length-extension resonators have already been used to obtain atomically-resolved images by frequency-modulation atomic force microscopy. Other piezoelectric materials such as gallium orthophosphate (GaPO(4)), langatate (LGT), and langasite (LGS) could be appropriate for this application. In this paper, the advantages of langasite crystal are presented and the fabrication of similar microsensors in langasite temperature-compensated cuts by chemical etching is proved. A monolithic length extension resonator, with a tip at its end, is obtained which constitutes a real advantage in regard to the existing quartz devices.  相似文献   
152.
Some database schema is very complex and it changes more frequently than the past. On the other hands, in such application database as scientific database and decision-support database, the importance of ad-hoc queries is expected to increase. Therefore the ability of a system to support ad-hoc queries without knowing the database schema information is needed. In this paper, we will describe a method to create candidate structured queries with concept hierarchy using user-input keywords. We will create structured queries in the following step; first, we extract the schema items related to keywords, and second, we compose possible paths between schema items, thus formulate candidate SQL queries.  相似文献   
153.
Layer-by-layer (LBL) electrostatic assembly of polyelectrolytes is proving to be an increasingly rich and versatile technique for the formation of multilayered thin films with a wide range of electrical, magnetic, and optical properties. In the present work we synthesized a new non-linear optical (NLO) maleic acid copolymer containing Disperse Red 1 moieties, built-up multilayer assemblies by alternate adsorption of poly(allylamine hydrochloride) (PAH) and maleic copolymer derivative, and carried out an investigation on their second harmonic generation (SHG) properties. The resulting multilayer assemblies exhibit SHG which arises from the non-centrosymmetric alignment of the chromophores in the copolymer. The SHG signal increases with the number of chromophore-containing polymer layers, up to five layers. Further assembly reduces the signal.  相似文献   
154.
Sourdough fermentation has been shown to have numerous beneficial effects on bread quality, and nutritionally enhance soy‐supplemented bread by altering isoflavone chemical forms. Given this, the objective of this study was to compare the loaf quality and shelf life of sourdough and yeast‐leavened soy breads by various physical, thermal, and sensorial methods, and to assess the effects of fermentation by various microorganisms on isoflavone profile in dough and breads using high‐performance liquid chromatography analysis. Sourdough fermentation yielded a less extensible dough compared to yeast‐leavened soy dough (P < 0.001), and resulted in a harder bread crumb (P < 0.05) and lighter crust color (P < 0.001), compared to yeast‐leavened soy bread (Y‐B). Sensory analysis revealed a significantly higher overall liking of Y‐B compared to sourdough soy bread (SD‐B) (P < 0.001). Segmentation analysis of the cohort suggests that overall liking and bread consumption frequency may be determinants of Y‐B or SD‐B preference. SD‐B and Y‐B exhibited similar shelf‐life properties. Despite significantly different enthalpies associated with the melting of amylose‐lipid complexes, thermal analysis of the 2 soy breads stored for 10 d (ambient conditions) demonstrated no significant difference in water distribution and starch retrogradation (P < 0.05). Lastly, SD‐B was determined to have 32% of total isoflavones occurring in the aglycone form compared to 17% in Y‐B. These findings warrant further investigation of sourdough fermentation as a processing technique for quality and nutritional enhancement of soy‐based baked goods.  相似文献   
155.
Results examining the effects of tasting profile on dietary intake and health outcomes have varied. This study examined the interaction of sweet liker (SL) and supertaster (ST) (bitter taste test through phenylthiocarbamide [PTC]) status with incidence of metabolic syndrome. Participants (n = 196) as part of baseline testing in a behavioral weight loss study completed measures assessing SL and ST status, metabolic syndrome, and dietary intake. SLs were more likely to be African American. More women than men were STs. There was a significant interaction between ST and SL status as associated with metabolic syndrome, after adjustment for demographic characteristics. This interaction was also significantly associated with fiber and caloric beverage intake. Post hoc analyses showed that participants who were only an ST or SL appeared to have a decreased risk of having metabolic syndrome compared with those who have a combination or are neither taster groups (P = 0.047) and that SL + ST consumed less fiber than SL + non‐ST (P = 0.04). Assessing genetic differences in taster preferences may be a useful strategy in the development of more tailored approaches to dietary interventions to prevent and treat metabolic syndrome. Practical Application : Tasting profile, such as sweet liking (SL) or supertaster (ST), may be influenced by genetics, and therefore in turn, may influence dietary intake. The present study found an interaction between ST and SL status with incidence of metabolic syndrome and fiber and caloric beverage intake. Testing people for these tasting profiles may assist with tailoring dietary recommendations, particularly around fiber and caloric beverage intake, and provide a way to modify metabolic syndrome risk.  相似文献   
156.
We report here the development of a straightforward, sensitive, and quantitative NMR-based method for high-throughput characterization of carbohydrate structure and screening of carbohydrate active enzyme (CAZyme) specificity. Automated assays starting from gene library expression to carbohydrate structure determination directly from crude reaction media have been established and successfully used to screen a library of 4032 CAZymes obtained by combinatorial engineering, at a rate of 480 enzyme variants per day. This allowed one to accurately discriminate 303 enzyme variants with altered specificity. The results demonstrate the potential of high-throughput NMR technology in glycomics, to mine artificial and natural enzyme diversity for novel biocatalysts.  相似文献   
157.
张婷 《世界建筑》2007,(11):71-75
这个项目的任务是要以合理的造价为4个大小不一的家庭建造高标准的居住空间。其间,任一家庭都要尽可能多地得到来自两个朝向的好景观.一个是南边的3000m^2。的室外景观.另一个是北边的俯视城市的景观。这就决定了建筑将具有不同寻常的复杂的内部格局。4套公寓都可以通过两层高的入口大厅进入.每一套都有它们独立的单层或者两层的内部楼梯。  相似文献   
158.
A new family of succinate-based plasticizers, consisting of molecules with a linear alkyl chain capped with n-alkyl succinates on both ends, was evaluated as potential bio-based plasticizers for stiff polymers. The influence of the central and side alkyl chain lengths on the mechanical and thermal properties as well as the migration behavior of poly(vinyl chloride) (PVC)/plasticizer blends was evaluated. The central chain length had the greatest influence on plasticizer performance, with shorter chains leading to blends with higher stress at break and surface hardness, whereas long chains produced softer blends. An optimum chain central length of five carbon atoms was observed, with longer chains leading to reduced compatibility and exudation of the plasticizer at higher plasticizer concentrations. The entire family of plasticizers performed comparably or better than the commercial plasticizer di(2-ethylhexyl) phthalate (DEHP) when incorporated into the blend at concentrations of 20–60 parts per hundred resin (phr). Overall, the succinate-based plasticizers/PVC blends all exhibited equal or improved tensile properties (by up to 77%), surface hardness (reduced by up to 43%), glass transition temperature (reduced by up to 11°C), and migration into organic media (reduced by up to 38%) when compared with blends with DEHP at 40 phr.  相似文献   
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