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41.
聚己内酯-聚丙交酯-聚醚三元共聚高分子微粒及其降解的研究 总被引:2,自引:0,他引:2
用乳化- 溶剂蒸发法制备了聚己内酯- 聚丙交酯- 聚醚三元无规共聚物微粒,且与用相同方法制备的聚己内酯(PCL) 和聚己内酯- 聚醚嵌段共聚物微粒的形态进行了比较,讨论了材料的亲水性,以及三元无规共聚物中亲水性聚醚链段的长度及含量对所形成微粒形态的影响。研究结果表明,随着聚合物由疏水性向亲水性转变,所生成微粒的形态则从光滑、多孔、到不规则变化。证明了三元无规共聚物多孔微粒的形成是由于亲水的聚醚链段向水相取向所致。在37 ℃、pH7 .4 的缓冲液中进行了三元无规共聚物微粒的降解,结果表明,随着降解时间的延长, 三元无规共聚物的分子量逐渐下降,且其中的聚醚链段含量有明显的降低。 相似文献
42.
微波辐射条件下, μ-氧-双(三正丁基锡)分别与二苯乙醇酸、2-氯烟酸反应, 合成了三正丁基锡羧酸酯(n-Bu)3SnO2CR(H2O)[R:C(OH)Ph2 (1), C5NH3Cl (2)]。经IR、1H和13C NMR、元素分析及X-射线单晶衍射表征结构。配合物1、2均属正交晶系, 空间群分别为Pbca和P212121, 配基与中心锡原子均构成五配位畸变三角双锥构型。1和2晶体中, 存在着多种氢键作用, 分别连接扩展成二维和三维超分子网络。初步测试表明:1和2对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460增殖均有较强的抑制作用, 尤其对MCF-7、Hela、NCI-H460的抑制作用均大大优于卡铂, 且1的抗肿瘤活性更优于2。 相似文献
43.
The tri(2-chlorobenzyl)tin(IV) complex with 4-pyridinylcarboxylate ligand tri(o-chlorobenzyl)tin ester of 4-pyridinecarboxylic acid has been synthesized by the reaction of tri(2-chlorobenzyl)tin(Ⅳ) chloride with 4-pyridinyl carboxylic acid and characterized by elemental analysis, IR and ^1HNMR, and its crystal structure was determined by X-ray single-crystal diffraction. 相似文献
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Palash Jyoti Das Anil Barak Yusuke Kawakami Tharanikkarasu Kannan 《Journal of polymer science. Part A, Polymer chemistry》2011,49(6):1376-1386
ABA‐type amphiphilic tri‐block copolymers were successfully synthesized from poly(ethylene oxide) derivatives through anionic polymerization. When poly(styrene) anions were reacted with telechelic bromine‐terminated poly(ethylene oxide) ( 1 ) in 2:1 mole ratio, poly(styrene)‐b‐poly(ethylene oxide)‐b‐poly(styrene) tri‐block copolymers were formed. Similarly, stable telechelic carbanion‐terminated poly(ethylene oxide), prepared from 1,1‐diphenylethylene‐terminated poly (ethylene oxide) ( 2 ) and sec‐BuLi, was also used to polymerize styrene and methyl methacrylate separately, as a result, poly (styrene)‐b‐poly(ethylene oxide)‐b‐poly(styrene) and poly (methyl methacrylate)‐b‐poly(ethylene oxide)‐b‐poly(methyl methacrylate) tri‐block copolymers were formed respectively. All these tri‐block copolymers and poly(ethylene oxide) derivatives, 1 and 2 , were characterized by spectroscopic, calorimetric, and chromatographic techniques. Theoretical molecular weights of the tri‐block copolymers were found to be similar to the experimental molecular weights, and narrow polydispersity index was observed for all the tri‐block copolymers. Differential scanning calorimetric studies confirmed the presence of glass transition temperatures of poly(ethylene oxide), poly(styrene), and poly(methyl methacrylate) blocks in the tri‐block copolymers. Poly(styrene)‐b‐poly(ethylene oxide)‐b‐poly(styrene) tri‐block copolymers, prepared from polystyryl anion and 1 , were successfully used to prepare micelles, and according to the transmission electron microscopy and dynamic light scattering results, the micelles were spherical in shape with mean average diameter of 106 ± 5 nm. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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Abstract Abstract:?A number of 4‐aryloxymethyl pyrano[3,2‐c][1]benzopyran‐5‐(2H)‐ones 3(a–f) were prepared by refluxing 4‐chloromethyl pyrano[3,2‐c][1]benzopyran‐5‐(2H)‐ones 1(a,b) with o‐bromophenols 2(a–c) in acetone in the presence of anhydrous potassium carbonate and sodium iodide in 70–80% yield. Compounds 3(a–f) were then subjected to radical cyclization by refluxing with tri‐n‐butyltin chloride, sodium cyanoborohydride, and azobisisobutyronitrile (AIBN) in dry benzene for 4–5 h to give a cis‐diastereomeric mixture of [6,6]pyranopyran derivatives in 80–85% yield. 相似文献
48.
在甲醇中氧化双[三(2-甲基-2-苯基)丙基锡]分别与吡嗪-2-甲酸、吲唑-3-甲酸反应,合成了2个三(2-甲基-2-苯基丙基)锡含N杂环羧酸酯(PhCMe2CH2)3Sn[O2C(C4N2H3)](1)和(PhCMe2CH2)3Sn[O2C(C7N2H5)](2)。经IR、1H和13C NMR、元素分析和X-射线单晶衍射表征结构。配合物1属单斜晶系,空间群P21/n,晶体学参数:a=1.209 31(7)nm,b=1.818 15(11)nm,c=1.491 39(9)nm,β=93.567(3)°,Z=4,V=3.272 8(3)nm3,Dc=1.302 Mg·m-3,μ(Mo Kα)=0.812 mm-1,F(000)=1 328,R1=0.027 5,wR2=0.067 0。配合物2属三斜晶系,空间群P1。晶体学参数:a=1.153 10(7)nm,b=1.819 73(11)nm,c=2.620 40(16)nm,α=86.866(2)°,β=87.063(2)°,γ=73.332(2)°,Z=6,V=5.255 9(6)nm3,Dc=1.288 Mg·m-3,μ(Mo Kα)=0.762 mm-1,F(000)=2 112,R1=0.037 4,wR2=0.092 5。1和2的中心锡原子均为畸变四面体构型。通过分子间C-H…O和N-H…N氢键作用,配合物2形成环状三聚体结构;两相邻三聚体间,经C-H…π作用进一步扩展成为六聚体。热重分析结果表明,1和2具有良好的热稳定性,分别在210、240℃以下可以稳定存在。毒性测试的初步结果表明,配合物1、2对石螺急性毒性较小,具有较好的环境相容性,且1的毒性低于2和苯丁锡。 相似文献
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合成了 2 个丁二酮肟有机锡化合物:双(三(2-甲基-2-苯基丙基)锡)丁二酮肟配合物(C6H5C(CH3)2CH2)3Sn(ON=C(CH3)C(CH3)=NO)Sn(CH2C(CH3)2C6H5)3 (1)和二苄基锡氧氯丁二酮肟多核配合物[μ3-O-((C6H5CH2)2Sn)2(ON=C(CH3)C(CH3)=NOH)(O)Cl]2(2)。通过元素分析、红外光谱、核磁共振(1H、13C、119Sn)、差热分析和单晶X射线衍射对配合物进行了结构表征,对其结构进行量子化学从头计算,并进行了体外抗癌活性研究。结果显示:配合物1为通过配体丁二酮肟桥联的双锡核中心对称分子,锡原子均为四配位的畸变四面体构型;配合物2为通过氧原子和丁二酮肟配体桥联的四锡核中心对称多环聚合结构,锡原子分别为五配位的畸变三角双锥构型和六配位的畸变八面体构型。配合物对人肝癌细胞(HUH7)、人肺癌细胞(A549)、人表皮癌细胞(A431)、人结肠癌细胞(HCT-116)和人乳腺癌细胞(MDA-MB-231)均有较强的抑制活性。 相似文献
50.
Matthias Freytag Jörg Grunenberg Peter G. Jones Reinhard Schmutzler Prof. Dr. 《无机化学与普通化学杂志》2008,634(8):1256-1266
3,4,5,6‐Tetrachlorobenzo‐3‐(2,4,6‐tri‐tert‐butylphenyl)‐1,3,2‐dioxaphospholane ( 2 ) and benzo‐3‐(2,4,6‐tri‐tert‐butylphenyl)‐1,3,2‐dioxaphospholane ( 4 ), in which the reactive PIII‐center lies close to the sterically demanding Mes* group (Mes* = 2,4,6‐tri‐tert‐butylphenyl), were prepared from Mes*–Br and the corresponding P‐chloro‐phospholane. Compounds 2 and 4 reacted with various oxidants, azides, MeSO3CF3 or [(tht)AuCl] (tht = tetrahydrothiophene) to give the expected products. All crystal structures of the products display a strongly distorted Mes* system with a boat conformation of the phenyl ring and appreciable out‐of‐plane deviations of phosphorus and the ortho‐tert‐butyl groups to opposite sides of the ring. Quantum chemical calculations at the DFT (density functional theory) level of theory were used in order to discriminate between intra‐ and intermolecular forces, which are responsible for these distortions. 相似文献