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201.
Yupeng Wu Yangchun Tao Kuan Cai Siwei Liu Yi Zhang Zhenguo Chi Jiarui Xu Yen Wei 《中国化学》2015,33(12):1338-1346
Two triblock polymers, tetraaniline‐block‐poly(N‐isopropyl acrylamide)‐block‐poly(hydroxyethyl acrylate) (TA‐b‐PNIPAM‐b‐PHEA) and TA‐b‐PHEA‐b‐PNIPAM, were synthesized with unambiguous structure by a two step method. The difference of these two diblock polymers is the connection order of carboxyl group to block, e.g., carboxyl group to PNIPAM block for PNIPAM‐b‐PHEA and to PHEA block for PHEA‐b‐PNIPAM. Secondly, block tetraaniline was linked to the diblock polymer through amidation to yield the corresponding triblock copolymer. Both of them have almost the identical chemical compositions. The only difference is the connection order of each block in the triblock polymers. When they were self‐assembled at 45°C in a suitable solution, both of their aggregates have spherical shape with slight defects on their surface with the average diameter of about 400 nm. However, when their aggregate dispersion was cooled down to 20°C, only TA‐b‐PHEA‐b‐PNIPAM's morphology changed, forming worm‐like aggregates with the diameter of about 100–200 nm transformed from spherical aggregates. Both amphiphilic property and position of each block in this triblock copolymer are very essential for this morphology transformation. Since the worm‐like aggregates presented here by our group have hollow structure inside, its controlled release properties for doxorubicin were evaluated. Drug release experiment indicated that along with the temperature changes, the rearrangement of the intermediate layer structure caused morphology change in aggregate, thus accelerating the speed of drug release. 相似文献
202.
Functional organic molecular materials and conjugated oligomers or polymers now allow the low-cost fabrication of thin films for insertion into new generations of electronic and optoelectronic devices. The performance of these devices relies on the understanding and optimization of several complementary processes. Our goal is to discuss the relationship between the molecular stacking structures and their optoelectronic properties that are of importance in all these areas. The concept of intermolecular interaction should be taken here in the special sense that is inter-dipole coupling. Specifically, we will address the impact of inter-dipole interaction between adjacent molecules in aggregate state on the solid-state emission properties. 相似文献
203.
TONG Yi-Ping 《结构化学》2007,26(1)
The zinc(Ⅱ) complex with Hpbx (Hpbx = 2-(benzoxazol-2-yl)phenol) and Hpbm (Hpbm=2-(benzimidazol-2-yl)phenol),namely[Zn(pbm)2]1.633[Zn(bpx)2]2.367·DMF·2H2O1,has been synthesized and characterized by X-ray crystallography,FTIR and elemental analysis.The coordination structures are statistically disordered and can be regarded as a co-crystal of [Zn(pbm)2]and [Zn(pbx)2] with the ratio of ca.0.408/0.592.Solvate water and DMF molecules are also present in the lattice.Crystal data for 1:monoclinic,space group P21/c,Mr= 2049.02,Z = 2,α = 9,7571(6),b = 25.6415(16),c = 19.8675(10)(A),β = 111.342(2)°,V = 4629.7(5) (A)3,Dc = 1.470 g/cm3,μ =1.100 mm-1,F(000) = 2104,R = 0.0575 and wR = 0.1282 for 5528 observed reflections (I> 2σ(I)).The photoluminescent spectra for this compound have also been studied. 相似文献
204.
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206.
利用水热合成方法制备了组成为[Cu(en)(H2O)(2,2′-bipy)]2H3BW12O4.02.5H2O的多金属氧簇有机-无机复合物,并用元素分析、IR和UV光谱、XPS、TG、荧光光谱、X射线单晶衍射对化合物进行了表征和性质研究.该化合物属于单斜晶系,P2(1)/c空间群,a=1.951 1(2)nm,b=1.229 76(12)nm,c=2.505 9(3)nm,β=91.266(2)°,V=6.011 1(11)nm3,Z=4.化合物阴离子[BW12O40]5-与配位阳离子[Cu(en)(H2O)(2,2′-bipy)]+通过静电作用相结合.XPS表明化合物中Cu、W氧化态分别为+1和+6价. 相似文献
207.
用硫酸钴、4,4'-联吡啶和2-磺酸基乙基膦酸合成了一个新颖的钴化合物:[Co_2(H_2O)_8(C_(10)H_8N_2)_2]·(HO_3PCH_2CH_2SO_3)(SO_4)(H_2O)_4,并对其进行了红外.元素分析、热重测试,通过单晶衍射仪测定了其晶体结构.结果表明,配合物属单斜晶系C2/c空间群,分子式为C_(22)H_(45)Co_2N_4O_(22)PS_2,分子量为930.57,晶胞参数为a=19.8456(18),b=11.2957(10),c=34.719(3)(A),β=106.095(3)°,晶胞体积为7477.9(12)(A)~3,Z=8,Dc=1.653 g/cm~3,F(000)=3856,μ=1.131 mm~(-1),最终残差因子R_1=0.0726,wR_2= 0.1719(相对于5612个I>2σ(I)的可观测衍射点).在这个化合物中,二齿配体4,4'-联吡啶把Co(II)桥连成[Co(4,4'-bipy)]~(2+)链.化合物中的[Co(4,4'-bipy)]~(2+)链有三个不同的朝向.2-磺酸基乙基膦酸没有参与配位而是做为一个有机模板剂填充在[Co(4,4'-bipy)]~(2+)链形成的空隙中. 相似文献
208.
三相中空纤维液相微萃取在羟基苯甲酸类化合物分析中的应用 总被引:1,自引:1,他引:1
在优化的三相中空纤维液相微萃取(3p-HFLPME)条件下,研究了6种羟基苯甲酸类化合物(HBAs)的3p-HFLPME行为;揭示了HBAs的富集因子(EF)与其正庚醇/水条件分配系数(log Pn-heptanol/5 mmol/L HCl)、pKa和羟基数目(N)的相关性,初步阐明了聚偏氟乙烯中空纤维对HBAs的电荷转移传递机理以及有机溶剂对HBAs的选择性萃取机理。优化的3p-HFLPME条件: 以MOF 503聚偏氟乙烯中空纤维为有机溶剂支持体,正庚醇为有机相,5 mmol/L HCl体系为给体,80 mmol/L NH3·H2O为接受相,搅拌速度为1200 r/min,萃取35 min。该方法的精密度(以相对标准偏差计)小于3%,检出限为0.09~30.00 μg/L,加标回收率为93.3%~107.1%,HBAs质量浓度为5 mg/L时的富集因子最高达107.6倍。 相似文献
209.
双马来酰亚胺增韧研究Ⅱ.链扩展双马来酰亚胺及其树脂的合成及表征 总被引:6,自引:0,他引:6
合成了一系列结构不同和链长短不一的双马来酰亚胺,并对其结构和性能作了表征,同时研究了它们的固化反应和固化产物的性能。用双马来酰亚胺和二烯丙基化合物反应制造了增韧树脂,研究了该树脂的固化和热稳定性。 相似文献
210.
The covalently -(CH2)10- linked eosin-butylviologen compound has been synthesized. The photoinduced electron transfer of eosin ester and butylviologen as well as the influence of addition of cyclodextrin or amylose into the solution of linked compound on the system have been studied by the absorption spectra, fluorescence spectra and fluorescence lifetime. The results indicated that the intramolecular electron transfer is much more efficient than the intermolecular one. Due to the formation of inclusion complex, the process of intramolecular electron transfer was changed after adding cydodextrin or amylose. 相似文献