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941.
Boiling water resistance, an important indicator of wood adhesives, represents the capability of adhesives for exterior woodwork applications. However, soy‐based adhesives show poor behaviors in this respect, which limit their applications in outdoor environments. In this article, we report a synergistic modification method of integrating a cocrosslinking system of epoxied polyamideamine‐epichlorohydrin (PAE) and organosilicon–acrylate copolymer latexes (OACLs) to improve soybean meal (SM)‐based adhesive properties. Tailored PAE and OACL SM‐based adhesives demonstrated robust crosslinking structures via multi‐interfacial interactions, where PAE and OACL served as building blocks of an interpenetrating network, which was characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The dry‐shear strength, wet‐shear strength, and boiling water strength of the resulting SM‐based adhesives were 1.41 ± 0.13, 1.32 ± 0.17, and 1.20 ± 0.11 MPa, respectively, with 15 wt % OACL loading; these were 41, 45, and 90% increases, respectively, over the SM–PAE adhesive with which we compared them. Most importantly, the excellent boiling water resistance of the adhesives make them practical for exterior plywood. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46061.  相似文献   
942.
Fully renewable soy protein isolate (SPI)–based film with rigid strength and sufficient water resistance is difficult to attain. In this study, the mussel‐inspired surface chemistry of ?‐poly‐L‐lysine (?‐PL)/dopamine was exploited for codeposition onto halloysite nanotubes (HNTs) to engineer a multinetwork of HNT/SPI bionanocomposite films via physicochemical bonds. A series of ?‐PL/dopamine aqueous solutions at different concentration ratios were employed. The ?‐PL with abundant cationic amine groups could prevent the overoxidation of dopamine on HNT surfaces, thus maintaining sufficient free catechol groups for highly active reactions that improve the biphase interfacial adhesion. Moreover, HNTs surface entangled by ?‐PL chains could be more compatible with peptides. This codeposition of ?‐PL/dopamine on HNT (DLHNT) surfaces was analyzed by X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, and thermogravimetric analysis. Compared to the control SPI film, the tensile strength of the nanocomposite film (DLHNTs0.5/SPI) was increased from 5.9 MPa to 8.25 MPa, the Young's modulus was improved by 166.4%, and the moisture absorption was reduced to 56.1% (87.2% of the control). In summary, a facile and mild bioinspired surface chemistry of ?‐PL/dopamine codeposition onto HNT surfaces was performed to prepare SPI‐based nanocomposite films with improved interfacial adhesion and benign compatibility. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46197.  相似文献   
943.
A ladder-type poly(3,4-ethylenedioxythiophene)-poly (ethylene glycol)-polyurethane (PEDOT-PEG-PU) supramolecular network was successfully synthesized using graft copolymerization of hydroxymethyl-EDOT with isocyanate-terminated PEG-PU prepolymer. PEDOT functionalized as the frame for a ladder-type supramolecular structure and PEG-PU as the rung. The successful formation of supramolecular network was confirmed by analyzing the Fourier transform infrared spectroscopy (FTIR). A series of PEDOT-PEG-PU gel polymer electrolyte by linking the LiClO4 were prepared as a function of [O/Li+] ratios. The pH effect of their electrical capacitances was investigated using cyclic voltammetry. Ionic conductivities of different PEDOT-PEG-PU/Li+ complexes at a fixed pH were also evaluated through impedance analysis.  相似文献   
944.
The effect of the ZnO/MgO ratio on the crystallization and optical properties of glass‐ceramic glazes from the SiO2–Al2O3–ZnO–MgO–CaO–K2O–Na2O–B2O3 system was studied. The glazes with different ZnO/MgO ratios were characterized by differential scanning calorimetry, X‐ray powder diffraction, Raman spectroscopy, scanning electron microscopy, energy dispersive spectroscopy analysis and a spectrophotometer. The results reveal that the A glaze without ZnO content contains forsterite and sapphirine. The B and C glazes with intermediate ZnO/MgO ratio contain enstatite and spinel solid solution. The D to F glazes with higher ZnO/MgO ratio crystallize spinel solid solution as the only crystalline phase. The amount of spinel solid solution, lightness values (L*), gloss values and the reflectance of the studied glazes increase with the ZnO/MgO ratio.  相似文献   
945.
Cu-Zn-Al催化剂上糠醛气相加氢制糠醇的研究   总被引:3,自引:0,他引:3  
Mn改性Cu Zn Al催化剂是糠醛气相加氢制糠醇的有效催化剂 ,在较温和的条件下 (氢醛比 :9;糠醛液体空速 :1 0h-1;反应温度 :130℃ ) ,糠醛转化率为 99 8% ,糠醇选择性 97 7%。K助剂的浸入可进一步提高糠醇的选择性。工业侧线运行结果表明 ,Cu Zn Al催化剂有较好的活性  相似文献   
946.
二氧化氯在水厂灭藻除嗅的应用   总被引:5,自引:0,他引:5  
本文总结了在水厂用二氧化氯取代氯气,夏季用于滤前灭藻除嗅,找到了二氧化氯的最佳投加浓度,并与氯气的使用效果进行了对比,结果表明投加二氧化氯需要的浓度低,使用效果明显优于氯气。  相似文献   
947.
研究了以Ce(SO4)2·2H2O作催化剂,丙二酸和正丁醇为原料合成丙二酸二丁酯,结果表明醇酸比为2.51,催化剂用量为1.0g,带水剂环己烷为30mL,反应时间为2h是最适宜的反应条件,酯化率可达97.3%.  相似文献   
948.
The formation of covalent bonds between silanols in copolymer and those in silica prevents organic–inorganic phase separation. Two series of hybrid composite materials, poly(vinyl acetate‐co‐vinyl trimethoxysilane)/TEOS and poly[vinyl acetate‐co‐3‐(trimethoxysilyl)propyl methacrylate]/TEOS, were fabricated using a modified sol‐gel process. The hybrids were transparent. Two kinds of silane coupling agents, vinyl trimethoxysilane (VTS) and 3‐(trimethoxysilyl)propyl methacrylate (γ‐MPS), were used to prevent macrophase separation through formation of covalent bonds. Thermal analysis showed that γ‐MPS was more effective than VTS for the formation of covalent bonds. Enhancement of thermal stability of the hybrids was investigated by thermogravimetric analysis. Photomicrographs of scanning electron microscopy and images of atomic force microscopy indicated that inorganic silica particles were homogeneously dispersed in less than 50 nm in organic matrix. The morphological properties of hybrids were strongly dependent on the organic–inorganic composition. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2310–2318, 2001  相似文献   
949.
Melt‐spun poly(trimethylene terephthalate) (PTT) fibers were zone‐drawn and the structures and properties of the fibers were investigated in consideration of the spinning and zone‐drawing conditions. The draw ratio increased up to 4 with increasing drawing temperature to 180°C, at a maximum drawing stress of 220 MPa. Higher take‐up velocity gave lower drawability of the fiber. The PTT fiber taken up at 4000 rpm was hardly drawn, in spite of using maximum drawing stress, because a high degree of orientation had been achieved in the spinning procedure. However, an additional enhancement of birefringence was observed, indicating a further orientation of PTT molecules by zone drawing. The exotherm peak at 60°C disappeared and was shifted to a lower temperature with an increase in the take‐up velocity, which means that the orientation and crystallinity of the fiber increased. The d‐spacing of (002) plane increased with increasing take‐up velocity and draw ratio, whereas those of (010) and (001) planes decreased. In all cases, the crystal size increased with take‐up velocity and draw ratio. The cold‐drawn PTT fiber revealed a kink band structure, which disappeared as the drawing temperature was raised. The physical properties of zone‐drawn PTT fibers were improved as the draw ratio and take‐up velocity increased. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3471–3480, 2001  相似文献   
950.
A new monomer, exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalimidocaproic acid (ETCA), was prepared by reaction of maleimidocaproic acid and furan. The homopolymer of ETCA and its copolymers with acrylic acid (AA) or with vinyl acetate (VAc) were obtained by photopolymerizations using 2,2‐dimethoxy‐2‐phenylacetophenone as an initiator at 25 °C. The synthesized ETCA and its polymers were identified by FTIR, 1H NMR and 13C NMR spectroscopies. The apparent average molecular weights and polydispersity indices determined by gel permeation chromatography (GPC) were as follows: Mn = 9600 g mol?1, Mw = 9800 g mol?1, Mw/Mn = 1.1 for poly(ETCA); Mn = 14 300 g mol?1, Mw = 16 200 g mol?1, Mw/Mn = 1.2 for poly(ETCA‐co‐AA); Mn = 17 900 g mol?1, Mw = 18 300 g mol?1, Mw/Mn = 1.1 for poly(ETCA‐co‐VAc). The in vitro cytotoxicity of the synthesized compounds against mouse mammary carcinoma and human histiocytic lymphoma cancer cell lines decreased in the following order: 5‐fluorouracil (5‐FU) ≥ ETCA > polymers. The in vivo antitumour activity of the polymers against Balb/C mice bearing sarcoma 180 tumour cells was greater than that of 5‐FU at all doses tested. © 2001 Society of Chemical Industry  相似文献   
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