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71.
Oil pollution is a crucial issue that has adversed impact not only on the environment but also human beings. As an alternative to all conventional approaches, a porous rubber gel based on liquid natural rubber (LNR) with excellent hydrophobic and wettability properties has been developed using a simple vulcanization reaction. To determine their sorption capability, LNR gel was employed for absorption of various types of oils such as Petrol A, Petrol B, kerosene, diesel, crude oil, and olive oil. The functionality of LNR gel was characterized by Fourier transform infrared spectroscopy and the morphology of LNR gel was observed using a scanning electron microscope. By combining wettability and hydrophobicity, the LNR gel exhibited high oil sorption capacity and selectivity for oil removal from water. The LNR gel was able to absorb oils, especially the low viscosity types. Besides, it can also be reused up to 20 cycles while maintaining its oil sorption performance. The selective absorbent shows the recovery of petrol in the range of 96–99% by squeezing the oil. Thus, LNR gel has great potential as green material for cleaning up oil contaminants on a large scale. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47749.  相似文献   
72.
Perchlorate is a naturally occurring inorganic anion used as a component of solid rocket fuel, explosives, and pyrotechnics. Sufficiently high perchlorate intakes can modify thyroid function by competitively inhibiting iodide uptake in adults; however, little is known about perchlorate exposure and health effects in infants. Food intake models predict that infants have higher perchlorate exposure doses than adults. For this reason, we measured perchlorate and related anions (nitrate, thiocyanate, and iodide) in 206 urine samples from 92 infants ages 1-377 days and calculated perchlorate intake dose for this sample of infants. The median estimated exposure dose for this sample of infants was 0.160 μg/kg/day. Of the 205 individual dose estimates, 9% exceeded the reference dose of 0.7 μg/kg/day; 6% of infants providing multiple samples had multiple perchlorate dose estimates above the reference dose. Estimated exposure dose differed by feeding method: breast-fed infants had a higher perchlorate exposure dose (geometric mean 0.220 μg/kg/day) than infants consuming cow milk-based formula (geometric mean 0.103 μg/kg/day, p < 0.0001) or soy-based formula (geometric mean 0.027 μg/kg/day, p < 0.0001), consistent with dose estimates based on dietary intake data. The ability of perchlorate to block adequate iodide uptake by the thyroid may have been reduced by the iodine-sufficient status of the infants studied (median urinary iodide 125 μg/L). Further research is needed to see whether these perchlorate intake doses lead to any health effects.  相似文献   
73.
Liza M  Chico Y  Fresnedo O  Ochoa B 《Lipids》2003,38(1):53-63
To address the role of cell membrane neutral sphingomyelinase (EC 3.1.4.12; SMase) in the regulation of cholesterol metabolism in the liver parenchymal cell, we examined the effect of exogenous neutral SMase on the metabolism of cholesteryl esters and the secretion of VLDL and biliary lipids in isolated rat hepatocytes. We show that treatment of hepatocytes with SMase (20 mU/mL) resulted in the intracellular buildup of cholesteryl esters, increased ACAT (EC 2.3.1.26) activity without affecting the ACAT2 mRNA level, and increased cytosolic and microsomal cholesteryl ester hydrolase (EC 3.1.1.13) activity. This was accompanied by increases in the secretion of biliary. bile acid, phospholipid, and cholesterol and in increased cholesterol 7α-hydroxylase (EC 1.14.13.17) activity and levels of mRNA, as well as decreased levels of apoB mRNA and a decreased secretion of VLDL apoB (apoB-48, ∼45%; apoB-100, ∼32%) and lipids (∼55%). Moreover, the VLDL particles secreted had an abnormal size and lipid composition; they were larger than controls, were relatively enriched in cholesteryl ester, and depleted in TG and cholesterol. Cell-permeable ceramides did not replicate any of the reported effects. These findings demonstrate that the increased cholesteryl ester turnover, oversecretion of biliary cholesterol and bile acids, and undersecretion of VLDL cholesterol and particles are concerted responses of the primary hepatocytes to exogenous neutral SMase brought about by regulation at several levels. We suggest that plasma membrane neutral SMase may have a specific, ceramide-independent effect in the regulation of cholesterol out-put pathways in hepatocytes.  相似文献   
74.
Alzheimer’s disease is a widespread and devastating neurological disorder associated with proteotoxic events caused by the misfolding and aggregation of the amyloid-β peptide. To find therapeutic strategies to combat this disease, Drosophila melanogaster has proved to be an excellent model organism that is able to uncover anti-proteotoxic candidates due to its outstanding genetic toolbox and resemblance to human disease genes. In this review, we highlight the use of Drosophila melanogaster to both study the proteotoxicity of the amyloid-β peptide and to screen for drug candidates. Expanding the knowledge of how the etiology of Alzheimer’s disease is related to proteotoxicity and how drugs can be used to block disease progression will hopefully shed further light on the field in the search for disease-modifying treatments.  相似文献   
75.
Small-molecule heterocycles bearing orthogonal functionality have the potential to deliver diverse structural motifs that aid the drug-discovery effort. This work highlights how a readily assembled N-hydroxyethyl pyrazole trifluoroborate offers rapid access to architecturally distinct 5-6-6- and 5-7-6-fused tricyclic compounds. This chemistry is not only amenable to single compound synthesis, but also to high-throughput experimentation. It gives easy access to diverse compound arrays with various physicochemical and ADME profiles by fully automated library synthesis. The combination of the high-throughput experimentation with rapid testing of the compounds in an integrated physicochemical and ADME profiling workflow allows accelerated design of novel lead compounds in drug-discovery projects.  相似文献   
76.
Taking medication requires developing plans to accomplish the activity. This planning challenges older adults because of age-related cognitive limits and inadequate collaboration with health providers. The authors investigated whether an external aid (medtable) supports collaborative planning in the context of a simulated patient/provider task in which pairs of older adults worked together to create medication schedules. Experiment 1 compared pairs who used the medtable, blank paper (unstructured aid), or no aid to create schedules varying in complexity of medication constraints (number of medications and medication co-occurrence restrictions) and patient constraints (available times during the day to take medication). Both aids increased problem-solving accuracy and efficiency (time per unit accuracy) compared to the no-aid condition, primarily for more complex schedules. However, benefits were similar for the two aids. In Experiment 2, a redesigned medtable increased problem-solving accuracy and efficiency compared to blank paper. Both aids presumably supported problem solving by providing a jointly visible workspace for developing schedules. The medtable may be more effective because it externalizes constraints (relationships between medication and patient information), so that participants can more easily organize information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
This study examines the process of change in filial therapy, a type of play therapy, which engages parents as therapeutic agents in working with troubled children. Outcome studies have supported the efficacy of this approach in building parent-child relationships, reducing parenting stress, and reducing child behavior problems. The purpose of this qualitative study is to examine the process in order to understand how these changes occur. The researchers compare the viewpoints of the therapist, the parents, and an independent observer, noting the points in therapy which are deemed facilitative or inhibitive of change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
In South Africa, households which earn too much to qualify for South Africa’s impressive capital subsidy programme and too little to access mortgage finance are referred to as the gap market. As the gap continues to grow, address is of increasing policy priority, a focus of local and national efforts. However, this paper argues that the gap market has been misunderstood and inappropriately framed in South African housing policy discourse. The case study of the City of Cape Town’s ‘Sale of Serviced Erven for GAP Market Purposes’ demonstrates the assumption that the gap market is a functional housing submarket which can be targeted uniformly. This paper argues that the gap market is instead a derivative of South Africa’s housing policy history and premised on the problematic ‘ownership imperative’. While the gap market is a useful conceptual tool to be understood within its historic trajectory, it should be discarded from policy design processes and replaced with more useful categories driven by analysis of the households and dynamics which comprise the market. This argument is relevant for all countries which seek to address gaps in their housing markets.  相似文献   
79.
This study examines the influence of packaging design on taste impressions. Building forth on research addressing transfer effects of symbolic associations from one sense to another, in this study it was studied if, and to what extent, potency-related associations portrayed by shape curvature and color saturation of yoghurt packages transfer to subsequent taste experiences. Furthermore, the influence of participants’ sensitivity to design was taken into account. Data were collected during a field study in the entrance hall of a large supermarket. Results indicate that associations portrayed by shape curvature in particular transfer to taste experiences, but that these effects are most pronounced for participants with a sensitivity to design. In addition, the findings presented indicate that shape curvature and color saturation may impact more general product evaluations and price expectations as well.  相似文献   
80.
The aim of this study was to describe a structured approach to effectively reduce Salmonella Dublin prevalence in infected dairy herds based on a step-wise procedure. Furthermore, the aim was to describe tools for management and monitoring, and to report on development in prevalence among young stock and adult cattle in 10 case herds that were followed for more than three years.The five steps in the structured approach were: 1) risk scoring to determine transmission routes within the herd and into the herd; 2) determining a plan of action; 3) performing management changes to close important routes of infection; 4) interpretation of repeated testing of individual animals to detect high-risk animals for special hygienic management or culling; and 5) diagnostic testing of different age groups and bulk tank milk to evaluate progress of control over time.Serology, true prevalence estimates and changes in herd classification in the Danish surveillance programme for Salmonella Dublin were used to assess the progress in the herds during and after the control period. Effective control of Salmonella Dublin was achieved in all participating herds through management that focused on closing infection routes mainly in the calving areas and the young calf areas of the herds. It took on average three years to control the infection in the case herds. Bulk tank milk recordings from the four following years indicated that most of the herds might have eradicated the infection.  相似文献   
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