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141.
Abstract

In this work the effect of cotton yarn properties on yarn end breakage was investigated. The yarn nominal linear densities were 20, 25 and 36 tex and each of them, had three levels of twists. Following yarn properties were investigated: linear density, twists, tensile strength, elongation at break and irregularity. Standard methods were applied to determine these yarn properties and hronometric method for yarn end breakage was used. It was only the yarn linear density, among all yarn properties, that showed significant correlation with yarn end breakage (-0,75 to -0,96). It was shown that about 80% of all yarn end breakage are occurred in places with fineness lower than average cross section of the yarn that point out that the thin places of the yarn are inclined to breaking. Also, the mutuality effect of geometrical characteristics and physical-mechanical properties of the yarn on end breakage was investigated.  相似文献   
142.
FeO-doped TiO2 nanoparticle photocatalysts were immobilized onto the surface of fibrous activated carbon (ACF) via a sol-gel process. As an adsorbent and photocatalyst, FeO-TiO2 on immobilized ACFs (FeO-TiO2/ACF) greatly improved the photocatalysis rate of hydrogen production as compared with pure TiO2 and ACF-TiO2 under UV irradiation and visible light. The addition of ACFs surface significantly reduced the photogenerated pairs of electrons-hole recombination, thereby promoting the photocatalysis action of doped photo-metal oxides of FeO-TiO2. Co-doping of FeO onto the lattice of the TiO2 approach can improve the absorption activity of visible light through photo-metal oxide of TiO2 and further enhance hydrogen production under visible light. The photocatalytic fabrics (FeO-TiO2/ACF) were effortlessly split out from the experimental solution for re-utilization and exhibited high stability even after five complete regeneration cycles.  相似文献   
143.
A novel cyclic‐amine monomer, 3‐allyl‐5,5‐dimethylhydantoin (ADMH) was synthesized and characterized. ADMH alone could not be grafted onto ordinary polymers. However, the presence of triallyl‐1,3,5‐triazine‐2,4,6(1H,3H,5H)‐trione (TATAT) remarkably enhanced the ADMH grafting yield onto synthetic fabrics. The influences of reaction conditions on the grafting copolymerization were investigated. After chlorine bleach treatment, hydantoin units in the grafted copolymers were transformed into N‐halamine structures. Treated samples exhibited potent antibacterial activity against Escherichia coli, and the functional properties were shown to be durable and regenerable. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1517–1525, 2001  相似文献   
144.
对几种玻璃纤维织物增强酚醛树脂复合材料进行了双向滑动摩擦试验,考察织物结构和基体树脂对复合材料的摩擦磨损性能的影响。研究结果表明:通过添加自润滑颗粒可提高复合材料的摩擦磨损性能,其中石墨的耐摩擦磨损效果比聚四氟乙烯(PTFE)显著;织物结构对复合材料摩擦性能的影响,主要受控于织物的表面粗糙度和织物结构对复合材料树脂体积分数的影响。此外,复合材料存在一个较优的树脂体积分数范围,在此范围内,复合材料的摩擦磨损性能较为优异。  相似文献   
145.
探讨了纯碱和氯化钠用量、染料浓度对微胶囊分散蓝2BLN/活性染料(活性蓝KN-R、活性深蓝B-2GLN和活性蓝K-3RL)一浴法染色大豆/PTT混纺织物表观色深K/S值的影响,测定了不同染色工艺对染色织物牢度的影响.结果表明:当染料总用量为2%(o.w.f.),纯碱用量1g/L,氯化钠用量20 g/L,95℃条件下保温30分钟时,可使大豆/PTT混纺织物获得较高的表观色深.  相似文献   
146.
Silk fabrics were modified by treatment with tannic acid (TA) solution or by acylation with ethylenediaminetetraacetic (EDTA) dianhydride. Kinetics of modification with TA and acylation with EDTA–dianhydride was investigated. The physico‐mechanical properties of silk fabrics acylated with EDTA–dianhydride remained unchanged regardless of chemical modification. The absorption of metal cations (Ag+, Cu2+) by untreated and modified silk fabrics was studied as a function of the kind of modifying agent, weight gain, and pH of the metal solution. The absorption of Cu2+ at alkaline pH was not significantly influenced by chemical modification of the silk substrate. The absorption of Ag+ by acylated silk remained at a level as low as untreated silk, while was enhanced by TA. The higher the content of TA, the higher the absorption of Ag+. With respect to the pH of the metal solution, the acylation with EDTA–dianhydride enabled silk to absorb and bind metal cations even in the acidic and neutral pH range, where tannic acid had no effect. Medium to high levels of metal desorption were exhibited by untreated and modified silk fabrics towards the metal cations, with the only exception of the silk–tannic acid–Ag complex, which displayed an extraordinary stability. All metal‐containing silks exhibited significant antibacterial activity. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 297–303, 2001  相似文献   
147.
自交联无纺布胶粘剂的研制   总被引:4,自引:0,他引:4  
以丙烯酸酯类为单体 ,采用复合乳化剂研制了自交联无纺布胶粘剂。介绍了配方、制备工艺及产品性能 ;讨论了配方组成、引发剂、乳化剂、交联组分等对胶粘剂性能的影响。  相似文献   
148.
Sodium N-dodecanoyl sarcosinate (SDDS), a novel amino-acid based surfactant, has immense biological and industrial importance. Although it is being used in a number of cosmetic formulations, systematic analysis of the bulk and interfacial properties of the surfactant is scarce in the literature. In this study, effects of salt, temperature, and pH on the self-association and related properties of SDDS have been examined in detail using methods such as tensiometry, conductometry, fluorimetry, pH-metry, spectrophotometry, calorimetry, and circular dichroism. The nature of amphiphilic packing and the aggregation numbers of the assemblies have been deciphered. Properties of the acid form of the surfactant have also been explored. The results have been conceptually rationalized and systematically presented together with associated energetics of the interfacial adsorption and self-aggregation of the surfactant in the bulk.
Satya P. MoulikEmail: Email:
  相似文献   
149.
A novel macroporous bead adsorbent, Fe(III)-loaded ligand exchange cotton cellulose adsorbent [Fe(III)LECCA], is synthesized for selective adsorption of arsenate anions [As(V)] from drinking water in batch and column systems. As(V) adsorption on Fe(III)LECCA was independent of pH, especially in drinking water pH range. Film diffusive control mechanism will benefit As(V) exchange with Fe(III)LECCA whether in batch or in column experiments. When treating the tap water at 26.0 BV/h, the column still preserves 83% of the original saturation adsorption capacity of the As(V) aqueous solution. These results have indicated that Fe(III)LECCA has the potential to act as an adsorbent for the removal of As(V) from drinking water considering its availability, nontoxicity and cost-effectiveness.  相似文献   
150.
本文对活性染料染锦/棉交织物的染色工艺进行了系统研究。根据活性染料的染色特征值SERF值从大到小的顺序筛选了三组活性染料,分别对先酸后碱工艺和应用pH值调节剂A工艺的染色效果作了比较研究。结果表明:SERF值中等的染料适用于上述两种工艺。先酸后碱工艺的固色率可达70%,摩擦牢度和皂洗牢度分别为4~5级,同色性较好。应用pH值调节剂A的工艺固色率可达80%,摩擦牢度和皂洗牢度分别为4~5级,且同色性较好。  相似文献   
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