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81.
本文以N-羟甲基丙烯酰胺、氯乙醇、三甲胺为原料合成了N-2(丙烯酰胺甲氧基)乙基三甲基氯化铵,这是目前国内尚没有开发的一种新型季铵盐,其共聚或均聚体分别是性能良好的纸干强剂或絮凝剂。本文以P—B实验设计法较全面考察了反应温度、反应时间、反应物配料比、硫酸加入量、碳酸氢钠加入量等诸因素对合成反应的影响,初步确定了影响反应产品收率的关键参数及其各自的较佳值,建立了在一定范围内适用的数学模型。 相似文献
82.
磷基FCC钝镍剂的开发及应用 总被引:1,自引:1,他引:0
工业试验表明 ,在催化裂化催化剂上的镍污染量高达 1%时 ,环境友好型磷酸盐钝镍剂仍能使汽油收率提高1% ,氢气产率和焦炭产率分别下降 35 %和 10 %以上 ,显示出良好的钝镍效果。结合轻油微反评价 (MAT)、TPR、XRD等实验方法和量子化学计算理论研究 ,阐明了磷基钝镍剂的钝镍机理 :在FCC再生条件 (约 70 0℃ ,氧化性气氛 )下 ,由于磷基钝镍剂热分解生成P2 O5,并与NiO反应生成NiP4O1 1 ,增加了Ni2 + 的能量最低空轨道 (LUMO)能量 ,降低了Ni2 + 在FCC(流化催化裂化 )反应条件 (约 5 0 0℃ ,还原性气氛 )下的还原度 ,有效抑制了Ni0 的强催化脱氢活性 ,从而达到钝镍的目的 相似文献
83.
84.
Physical properies of ion-conducting nanocomposites are reviewed. Special attention is paid to the change of the bulk characteristics of ionic salts in the nanocomposites due to the formation of the interface phases. The main thermodynamic reason of the formation of the nanocomposite as well as the stabilization of the interface phases is the adhesion energy a. At sufficiently high a values, the ionic salt tends to spread along the oxide surface, which leads to the formation of the nanocomposite on sintering. The adhesion is the result of the interface interaction and incorporates the stage of the specific adsorption of the interface ions. It leads to the formation of the double layer formed by the point defects in the interface region of the ionic salt. In the case of the strong adhesion, the structural reconstruction or the formation of the metastable interface phase takes place. Analysis of the experimental data shows that interface phases exist in composites AgI–Al2O3, MeNO3–Al2O3 (Me = Li, Na, K, Rb, and Cs), CsHSO4–SiO2, RbNO3–SiO2 and CsCl–Al2O3. Their structure may be either epitaxial crystalline, or amorphous. The thickness of the interface phase as estimated on the basis of the brick-wall model is about 3–4 nm. 相似文献
85.
The purpose of this study was to examine the effect of different concentrations of crude pig plasma transglutaminase (TGase) at 0, 0.05, 0.1, 0.2, 0.4 and 1.0% on the quality of low-salt chicken meat-balls. Yield, color, gel strength, microstructure and sensory evaluation were measured. The results showed that both the yield and gel strength of the meat-balls increased as TGase supplement increased (P<0.05) without any obvious effect on color. Scanning electron microscopy (SEM) indicated firmer and more regular gel structures with increasing TGase addition. Texture, juiciness and overall acceptability as judged by sensory evaluation were not statistically affected until the level of TGase reached 1.0% (P<0.05). 相似文献
86.
Transparency of Hydrophobic Vinyl Polymers Containing Small Amounts of Inorganic Chloride Salts 总被引:1,自引:0,他引:1
Termination of n-BuLi-initiated anionic polymerizations of vinyl monomers (i.e. styrene or butadiene) by chlorotrimethylsilae (CTMS) or methoxytrimethylsilane (MTMS) resulted in an opaque or transparent polymer product. Small amounts of salt (i.e. LiCl from CTMS- or Li(OCH3) from MTMS-terminated polymerization) generated during termination stage was presumably the cause of the transparency difference. To verify this, turbid solutions were prepared by mixing transparent polymers (prepared from a H2O-terminated anionic polymerization) with controlled amounts of LiCl in mixed tetrahydrofuran/cyclohexane (THF/CHE) solvents. Reduced viscosity (red) and particle size (determined from light scattering) of these turbid solutions were found to increase with polymer and LiCl content. On the contrary, both red and particle size decrease with increasing THF content of the mixed solvent. These results suggest that interactions between the LiCl/THF complex and the polymer chains are responsible for particle formation and hence turbid appearance of the solutions. Solution 7Li NMR spectra of the salt/polymer solutions indicated that polystyrene (PSt) has stronger interactions with LiCl as compared to polybutadiene (PBu), which resulted in a more homogeneously salt distribution in PSt than PBu as evaluated from the TEM micrographs of the corresponding bulk samples after solvent removal. A model with the included LiCl/THF complexes surrounded by the polymer coils was proposed to account for the resulting turbidity in solutions and in the bulk state. 相似文献
87.
The main problems arising in all far-from-equilibrium simulations come from temperature control. When local flows become important, it is not a simple matter to distinguish between the flow velocity and thermal motion. A way to bypass this problem is to control the temperature given by the configurational expression, which does not depend on velocity. The responses of molten NaCl to strong shear and strong constant and oscillating electric fields using kinetic and configurational thermostats are compared. The differences in response increase with the increase in the external perturbation, and in very strong fields one can observe striking structural differences. In the case of shear flow, the differences are of a general nature seen in all liquids (the appearance of a string phase with kinetic thermostats), while in an electric field they are peculiar to ionic fluids and are related to the degree of dissociation. Some structural properties can be deduced by evaluating the configurational temperature expression. 相似文献
88.
耐温抗盐聚合物TS-45流变性及驱油效率研究 总被引:4,自引:1,他引:3
在45℃(大庆主力油藏温度)下,以超高分子量(2.8×107)HPAM为对比,实验考察了耐温抗盐聚合物TS-45溶液的流变性能和驱油能力.TS-45为丙烯酰胺、强极性(含-SO3H)支链单体及少量疏水缔合单体的共聚物.实验聚合物溶液含盐(NaCl)5 g/L,含聚合物1 g/L.两种聚合物溶液在0.02~600 s-1范围均为假塑性流体,TS-45溶液的粘度大于HPAM溶液.溶液的G′和G″随振荡频率增加(0.1~50 Hz)而增大;TS-45的G′(和G″)大于HPAM的相应值;G′和G″曲线的交点,TS-45为0.1 Hz,此时G′=G″=0.078 Pa,HPAM为0.147 Hz,此时G′=G″=0.0088 Pa,表明TS-45溶液的弹性大于HPAM溶液.与NaCl浓度1 g/L的聚合物溶液相比,实验溶液的G′和G″均下降,在2.81 Hz下的保留率对于TS-45分别为48.2%和38.3%,对于HPAM分别为24.1%和17.2%,说明TS-45的耐盐性较好.TS-45在岩心中的阻力系数和残余阻力系数(38.6和9.6)大于HPAM的相应值(25.4和5.7).在岩心驱油实验中,注入0.38 PV聚合物溶液提高采收率的幅度,1 g/L的TS-45污水溶液、HPAM清水和污水溶液分别为12.6%、10.5%、8.9%,0.8 g/L的TS-45污水溶液为10.7%;在注入量0.2~2.0 PV范围内提高采收率的幅度,1 g/L的TS-45污水溶液恒大于HPAM污水溶液.图6表2参5. 相似文献
89.
90.
Lennart Åqvist 《Artificial Intelligence and Law》2007,15(4):391-410
The purpose of this paper is to improve on the logical and measure-theoretic foundations for the notion of probability in the law of evidence, which were given in my contributions Åqvist [ (1990) Logical analysis of epistemic modality: an explication of the Bolding–Ekelöf degrees of evidential strength. In: Klami HT (ed) Rätt och Sanning (Law and Truth. A symposium on legal proof-theory in Uppsala May 1989). Iustus Förlag, Uppsala, pp 43–54; (1992) Towards a logical theory of legal evidence: semantic analysis of the Bolding–Ekelöf degrees of evidential strength. In: Martino AA (ed) Expert systems in law. Elsevier Science Publishers BV, Amsterdam, North-Holland, pp 67–86]. The present approach agrees with the one adopted in those contributions in taking its main task to be that of providing a semantic analysis, or explication, of the so called Bolding–Ekelöf degrees of evidential strength (“proof-strength”) as applied to the establishment of matters of fact in law-courts. However, it differs from the one advocated in our earlier work on the subject in explicitly appealing to what is known as “Pro-et-Contra Argumentation”, after the famous Norwegian philosopher Arne Naess. It tries to bring out the logical form of that interesting kind of reasoning, at least in the context of the law of evidence. The formal techniques used here will be seen to be largely inspired by the important work done by Patrick Suppes, notably Suppes [(1957) Introduction to logic. van Nostrand, Princeton and (1972) Finite equal-interval measurement structures. Theoria 38:45–63]. 相似文献