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1.
Structural isomers of monoacylglycerols (monoglycerides, MAGs) were identified and compared after degradation of butter oil by two strains of Penicillium roquefortii and a commercial lipase from P roquefortii (EC 3.1.1.3) at pH 7.0 and 10 °C. The conditions were selected as they were comparable with those used in the manufacture of blue mould‐ripened cheese. The commercial lipase was selected to compare with the fungal strains in terms of acyl migration. Results showed that the main isomers formed by lipolysis with the commercial lipase were sn‐2 MAGs (64 mol%), whilst spores and emerging mycelia of P roquefortii produced mainly sn‐1(3) MAGs (83–90 mol%). The work reported here may lead to further assessment of different MAG structural isomers as natural preservatives in foods and dairy products. © 2002 Society of Chemical Industry  相似文献   
2.
This study describes a laboratory method for the estimation of emission from preservative-treated wood in the different situations where emissions could enter the environment for use classes 3 (not in contact with ground) and 4 and 5 (in contact with the ground, fresh water or sea water) according to OECD Guidelines. Samples of scotch pine sapwood (Pinus sylvestris L.) were treated with CCA (1% and 2%), ACQ-1900 (3% and 7%), ACQ-2200 (2%), Tanalith E 3491 (2% and 2.8%), and Wolmanit CX-8 (2%).  相似文献   
3.
An assessment of the pollution status of Museum Lake in the Thiruvananthapuram Botanical Garden and Museum was conducted. Analysis of different community structures of the planktonic taxa in the lake revealed it is organically polluted, attributable to the organic litter from riparian vegetation. A total of 30 most pollution‐tolerant phytoplankton genera and 24 pollution‐tolerant species were identified. Pollution‐tolerant phytoplankton genera in the lake included Chlorophyceae, Bacillariophyceae, Cyanophyceae and Euglenophyceae. Scenedesmus, Pinnularia, Euglena, Ankistrodesmus, Closterium, Crucigenia, Kirchneriella, Merismopedia and Oscillatoria were some of the phytoplankton pollution tolerant genera whereas, Nitzschia palea, Synedra acus, Scenedesmus quadricauda, Pandorina morum and Trachelomonas volvocina were some of the pollution tolerant species noted. Excessive nutrient loading from the surrounding area is definitely degrading the quality of this urban lake ecosystem. Detailed information regarding the pollution status of a waterbody is very important in this regard, noting it ultimately assists in undertaking proper management of a waterbody. The Palmer Algal Index score for Museum Lake was 37, indicating it is highly organic enriched. The results of different algal indices (e.g. Chlorophycean Index; Nygaard Index) indicated a eutrophic condition for Museum Lake, being attributed to its increased organic enrichment. Canonical correspondence analysis between environmental variables and the microalgal bioindicators also highlighted the influence of the physical and chemical parameters on phytoplankton abundance and distribution in Museum Lake.  相似文献   
4.
Chromated copper arsenate (CCA), an arsenicbased wood preservative, is toxic to human health and the environment. Although CCA is stable in seasoned wood, there are potential dangers during CCA manufacture, lumber treatment, and waste disposal. This research was conducted to study the effectiveness of soy products to replace toxic chromium and arsenic compounds in wood preservative formulations. Three soy product (Arpro 2100, HM 90, and Supro 760) were used as fixative agents in preservative solutions containing anhydrous CuSO4 and Na2B4O7·10H2O. The decay resistance of treated wood blocks was measured by a soil-block culture method. Despite the large molecular sizes of copper-protein and copper-boron-protein complexes, southern pine sapwood was treatable with these preservative formulations. Wood samples treated with >6 kg°m−3 CuSO4 and 7.5 kg·m−3 soy product, and subsequently leached for 3 d and exposed to the decay fungus Gloeophyllum trabeum (Fr.) Mur., sustained only 0.5% weight loss over 12 wk. Wood samples needed 40 kg·m−3 CuSO4 and 50 kg·m−3 soy protein to resist the copper-tolerant decay fungus Postia placenta (Fr.) M. Lars. & Lomb. These results suggest that soy-based wood preservatives can prevent wood products from fungal attack and can replace CCA.  相似文献   
5.
介绍了FDA的化妆品配方自愿登记计划(VCRP)及参与的好处,对《化妆品与盥洗用品》杂志公布的近30年来的的化妆品防腐剂使用频率数据进行了整理,描述了历次统计前20位品种的变迁,对一些重要品种,如重氮咪唑烷基脲、咪唑烷基脲、二羟甲基二甲基乙内酰脲、甲醛类、季铵盐-15、布罗波尔、异噻唑啉酮类、碘代丙炔基于基氨基甲酸酯(IPBC)、三氯生、苯氧乙醇和尼泊金酯类等的走势和应用进行了介绍。  相似文献   
6.
简要介绍了微生物对化妆品杀菌防腐剂的耐受性与抗药性概念、抗药性微生物种属特性、杀菌剂的抗性水平以及抗性的风险评估和治理措施,旨在为提高化妆品(日化产品)和美容美发产品的质量,保障广大消费者的身体健康,并为科学合理使用现有杀菌防腐剂和研究开发新型杀菌防腐剂提供科学依据。  相似文献   
7.
目的 为满足木包装材料的使用要求和防疫要求,需将木材进行防腐处理,但传统的防腐处理方式易对环境和物品造成污染,存在安全隐患,生物基防腐技术可解决上述问题。方法 介绍当前木包装材料的使用现状,阐述国内外生物基防腐技术的研究进展,并分析和讨论木包装材料在使用中存在的问题。结果 生物基防腐技术是一种绿色、高效的木材防腐技术,目前已取得了一定的研究成果。结论 生物基防腐技术可以满足木包装材料在运输和存储中的各种需求,并且具有环保无毒的优点,因而具有非常广阔的开发和应用前景。  相似文献   
8.
建设生态园林、生态城市首先要转变观念,要加强边缘科学研究,城与乡要拆墙,实现一体化;要把园林建设看作投资自然资本,为地球增加绿色,改善生存环境。  相似文献   
9.
Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use.  相似文献   
10.
选取乙醇和水作为溶剂萃取茴香中的茴香醛,探究了不同外在因素对提取效率的影响。实验结果表明,反应介质为6 mol/L的HCl,显色剂用量为2 mL,反应时间20 min,反应温度为室温时测定茴香醛最佳。在室温下,萃取茴香醛的最佳溶剂为无水乙醇;萃取温度为32℃且萃取时间为30天时,茴香醛的提取效率可达到最高,为2.45%,而水萃取茴香醛的含量就比较低,在萃取温度为55℃时,茴香醛的萃取效率仅为0.27%。结果表明,无水乙醇的提取效率比蒸馏水的提取效率高,两者相差高达20倍左右。  相似文献   
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