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101.
Hydrous ruthenium-tin oxides (denoted as (Ru-Sn)O2·nH2O) were synthesized under a mild hydrothermal condition. The mean particles size of pristine RuO2·nH2O, smaller than 3 nm, was decreased with the introduction of Sn into the precursor solutions while it is not significantly affected by varying the Sn content. The textual characteristics of (Ru-Sn)O2·nH2O were analyzed through means of X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), electron diffraction, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analyses (TGA). From the ideal capacitive behavior of pristine oxides with the Ru content ≥40 at.%, hydrothermal synthesis favored the formation of hydrous oxides with a novel structure providing excellent pathways for electron hopping and proton diffusion/exchange during the charge storage/delivery process. The introduction of tin oxide was demonstrated to successfully promote the utilization of oxyruthenium species, reaching a maximum CS,Ru of ca. 830 F/g for pristine Ru0.6Sn0.4O2·nH2O (measured at 25 mV/s).  相似文献   
102.
The effects of hydrothermal cooking (HTC) at alkaline conditions on refunctionalization of heat-denatured protein of extruded-expelled (EE) soy meals and on preparation of soy protein isolate (SPI) from EE soy meal were determined. Two HTC setups, flashing-out HTC (without holding period) and HTC with holding for 42 s at 154°C, were evaluated. Alkali (NaOH) addition dramatically enhanced the refunctionalization of EE meal having an initial protein dispersibility index of 35. The more alkali added, the more refunctionalization occurred. Extensive refunctionalization was achieved at 0.6 mmol alkali/g EE meal, and additional improvement was small with more alkali. For both HTC setups, the solids and protein yields of SPI from alkali-HTC-treated EE meals were significantly higher than those from HTC without alkali addition. The yield of protein as SPI increased from 40 to 82% after HTC treatment at 0.6 mmol alkali/g EE meal compared with no alkali addition. The emulsification capacities of SPI after alkali-HTC were similar to those from HTC without alkali. SPI from holding-tube HTC-treated EE meals had higher emulsification capacities than those prepared by flashing-out HTC.  相似文献   
103.
热液通过渗滤和浓度扩散作用在煤层中运移,使煤变成煤种单一的高变质煤。随煤变质程度增高,煤中的活泼金属元素迁出,并加入到热液中,而热液中的过渡金属系元素则被煤层部分吸收,使煤灰分向着降低和增加两个相反方向变化。与热液有关的金属矿床矿物中包裹体常含煤成气成分,说明煤成气参与了金属成矿作用。小规模高变质煤附近,常发现大型金属矿床和小型煤成气田;大规模高变质煤附近,常发现小型金属矿床(点)和大型煤成气田。  相似文献   
104.
厌氧消化(AD)耦合水热炭化(HTC)技术对园林废弃物的可持续资源化利用具有显著优势和意义。采用草为研究对象,进行了7~28 d的AD预处理,深入探究了AD预处理耦合HTC对水热炭特性及其热解和产物释放特性的影响。其中,AD促进HTC过程主要发生脱羧反应;通过改变木质纤维素构成比例和结构特征有效调控水热炭的功能特性。此外,AD打破了生物质内部致密的刚性结构,促进了水热炭丰富孔隙的形成和比表面积的增加。在生物可降解程度为17.52%(AD 7 d)时,水热炭性能最佳,质量产率、高位热值(HHV)、能量产率和能量密度分别达62.75%、23.81 MJ·kg-1、80.31%和1.28。此外, TG-MS分析结果揭示了AD预处理提高了炭的热稳定性以及热解产物中能源气体的生成,有助于热解气的提质和利用。  相似文献   
105.
In vitro, in vivo, and clinical studies have shown how the physicochemical and biological properties of β-tricalcium phosphate (β-TCP) work in bone regeneration. This study aimed to improve the properties of β-TCP by achieving optimum surface and bulk β-TCP chemical/physical properties through the hydrothermal addition of magnesium (Mg) and to later establish the biocompatibility of β-TCP/Mg for bone grafting and tissue engineering treatments. Multiple in vitro and in vivo analyses were used to complete β-TCP/Mg physicochemical and biological characterization. The addition of MgO brought about a modest rise in the number of β-TCP surface particles, indicating improvements in alkaline phosphatase (ALP) activity on day 21 (p < 0.05) and in the WST-1assay on all days (p < 0.05), with a corresponding increase in the upregulation of ALP and bone sialoprotein. SEM analyses stated that the surfaces of the β-TCP particles were not altered after the addition of Mg. Micro-CT and histomorphometric analysis from rabbit calvaria critical defects resulted in β-TCP/Mg managing to reform more new bone than the control defects and β-TCP control at 2, 6, and 8 weeks (* p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, and **** p ≤ 0.0001). The hydrothermal addition of MgO to the β-TCP surfaces ameliorated its biocompatibility without altering its surface roughness resulting from the elemental composition while enhancing cell viability and proliferation, inducing more bone regeneration by osteoconduction in vivo and osteoblastic differentiation in vitro.  相似文献   
106.
Magnesia-alumina layered double hydroxide (Mg-Al LDH) films grown in situ on LA43M magnesium-lithium (Mg-Li) alloy were synthesized utilizing the hydrothermal method. Scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and X-ray diffraction (XRD) were used to characterize the surface morphologies, composition, and phase of the Mg-Al films. The corrosion resistance of the Mg-Al films was estimated via immersion experiment and hydrogen evolution test, and the tribological properties were investigated using tribological wear tests. The results showed that the thickness of the Mg-Al LDH film enhanced, and the size of the LDH sheets increased as the hydrothermal temperature raised, resulting in the improvement of the corrosion and wear resistance. When the hydrothermal temperature reached 110°C, interlayer anions were loaded the most, and the film achieved the optimal thickness. The Mg-Al LDH film had the optimum corrosion resistance and tribological properties. At this point, the weight loss of the film was 1.3560 mg·cm–2, and the average friction coefficient was .149. It demonstrated that synthesizing Mg-Al LDH at a hydrothermal temperature of 110°C was an effective approach to improve the corrosion resistance of LA43M.  相似文献   
107.
This article reports spin coating and hydrothermal approaches to the synthesis of Cu2O seed layer−ZnO and Cu2O film−ZnO heterojunction films on fluorine-doped tin oxide substrates. Cu2O seed layers and an ethylene glycol (EG) reducing agent were employed to obtain pure, uniform, and adhesive Cu2O films on the substrate. Transmission electron microscopy validated the heterojunctions with clear interfaces between each component on the p-Cu2O film−n-ZnO (with EG) sample, the conductive types of which were determined through Mott−Schottky measurements. Constructed energy band diagrams supported the Mott−Schottky result, manifesting favorable conduction band positions for the generation of •O2 radicals for all constituent materials and indicating smooth charge carrier transport for the p-Cu2O film−n-ZnO (with EG) sample. Furthermore, abundant p−n junction interfaces synergistically enabled the sample to exhibit the most satisfactory photodegradation capability (rate constant ≈ 8.9 × 10−3 min−1), which was attributable to the predominance of •OH radicals. The sample's rectifying (diode) behavior with a ratio of the current density (J) at +3 V (forward bias) to that at −3 V (reverse bias) of approximately 27 was observed without ultraviolet illumination. Moreover, the J at −3 V is under illumination approximately 80 times that without illumination, implying the suitability of the sample for UV detectability.  相似文献   
108.
赵双生  应宗荣  杨佳佳  凡川 《化工学报》2016,67(11):4892-4898
采用三水合硝酸铜为铜源、硫脲为硫源、D-葡萄糖酸钠为络合剂,发展了简单的“一锅法”水热直接一步合成CuS/C复合材料。采用X射线衍射仪(XRD)、激光显微拉曼光谱仪(Raman)、扫描电子显微镜(SEM)和有机元素分析仪对复合材料组成、结构及形貌进行表征。研究发现,样品主要由花状CuS球组成,同时含有质量分数约为6%的光滑炭球,CuS球表面分布有花瓣状褶皱,形成的大量孔道有利于离子传输,并增大活性物质与电解液的接触面积。研究表明,在1 A·g-1电流密度下,比电容高达719 F·g-1,与不加络合剂制备得到的CuS(382 F·g-1)相比,比电容显著提高,并且在充放电1000次后比电容保持在80%左右,显示出良好的循环稳定性。  相似文献   
109.
以硅溶胶、硫酸铝、氢氧化钠和去离子水为原料,以N,N,N-三甲基金刚烷氢氧化铵和三乙胺为模板剂,采用传统的水热法快速合成了SSZ-13分子筛。采用X射线荧光光谱(XRF)、X射线衍射(XRD)和扫描电镜(SEM)表征产物。综合考察了碱度、水量、模板剂和晶种等因素对合成SSZ-13分子筛的影响,确定了最佳合成条件。在有晶种或无晶种条件下,通过引入辅助模板剂三乙胺,晶化2 d即可得到SSZ-13分子筛。该方法缩短了生产周期,降低了生产成本,具有广泛的工业应用前景。  相似文献   
110.
以青海盐湖地区高含泥提钾尾矿为起始原料,在无额外添加硅铝源的条件下,采用水热合成法及"液相转移"技术成功制备出纯度较高的Y型分子筛.通过X-射线荧光光谱(XRF),红外光谱(IR)、X-射线衍射(XRD)等手段对材料进行了表征,并考察了材料对水溶液中Cs+的吸附性能.结果表明,盐湖高含泥提钾尾矿是制备Y型分子筛的合适前驱体.该材料对低浓度溶液中的Cs+具有较好的吸附效果.  相似文献   
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