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91.
Meng-Han Wang Zhong-Yuan Xue Zhi-Wei Wang Wei-Hua Ning Yu Zhong Ya-Nan Liu Chun-Feng Zhang Sven Huettner You-Tian Tao 《高分子科学》2018,36(10):1129-1138
A series of random terpolymers P2-P5 were designed and synthesized by randomly embedding 5 mol%, 10 mol%, 15 mol%and 25 mol% feed ratios of low cost 2,2-bithiophene as the third monomer to the famous donor-acceptor(D-A) type copolymer PTB7-Th(P1). All polymers showed similar molecular weight with number-average molecular weight(Mn) and weight-average molecular weight(Mw) in the range of(59-74) and(93-114) kg·mol~(-1), respectively, to ensure a fair comparison on the structure-property relationships.Compared with the control copolymer PTB7-Th, the random terpolymers exhibited enhanced absorption intensity in a wide range from400 nm to 650 nm in both solution and film as well as in polymer/PC71 BM blends. From grazing incident wide-angle X-ray diffraction(GIWAXS), compared with the regularly alternated copolymer PTB7-Th, the random terpolymers demonstrated mild structural disorder with reduced(100) lamellar stacking and slightly weakened(010) π-π stacking for the polymers as well as slightly reduced PC71 BM aggregation in polymer/PC71 BM blends. However, the measured hole mobility for terpolymers((1.20-3.73) × 104-cm2·V-1·s~(-1)) was evaluated to be comparable or even higher than 1.35 × 10~(-4) cm~2·V~(-1)·s-1 of the alternative copolymer. Enhanced average power conversion efficiency(PCE) from 7.35% to 8.11% and 7.79% to 8.37% was observed in both conventional and inverted device architectures from copolymer P1 to terpolymers P4, while further increasing the 2,2-bithiophene feed ratio decreased the PCE. 相似文献
92.
Ya-Nan Luo Hui-Ying Jiang Zhi-Chen Liu Li-Ying Yu Xiao-Yang Yu 《Structural chemistry》2018,29(4):977-982
One new supramolecular compound based on H2L (H2L?=?4-[(8-hydroxy-5-quinolinyl)azo]-benzenesulfonic acid, C15H11O4N3S), [Zn3L2(OH)2(H2O)6]n (1), has been synthesized by hydrothermal technique. Compound 1 exhibits a one-dimensional (1-D) double-chain structure. Compound 1 is the first example of an azo complex used to co-sensitize TiO2 photoanode with Ru dyes (N719, N3). In the tandem structure of compound 1/N719/TiO2, compound 1 plays a significant role in the improvement of the photoelectric conversion efficiency, which works with N719 to modify the energy level. The results show that the compound 1/N719/TiO2 solar cell exhibited excellent photovoltaic performance with the photoelectric conversion efficiency of 7.1% under standard global AM 1.5 solar irradiation conditions. 相似文献
93.
P. S. Pa 《Journal of Solid State Electrochemistry》2008,12(11):1445-1451
An ITO layer is produced using semiconductor techniques, although the defect rate during production is easily seen. Current
work presents a new modus of electrochemical machining using a ‘design recycle’ system offering faster performance in removing
the color filter surface’s ITO layer. Higher electrical current is not required when an effective feeding electrode is used
to reduce the response area. Through establishing an ultra-precise recycling process to remove the thin film microstructure,
this helps the semiconductor optoelectronic industry to reduce both production costs and pollution. The design features of
the removal processes for a thin film and the tool design of plate-form electrode are of major interest. In the current experiment,
the author utilizes a 5th Generation TFT-LCD. The design of tool electrodes is used with continuous and pulsed direct current
in the electrochemical machining experiment. High rotational speed of the tool electrodes and high flow velocity of the electrolyte
elevates the discharge mobility and improves the removal effect. Pulsed direct current can improve the effect of dregs discharge
and is advantageous to associate with the fast feed rate of the workpiece. A color filter with a fast feed rate is combined
with enough electric power to provide highly effective removal. A smaller end radius and a thin plate-form positive-electrode
provide a larger discharge space and better removal effect. A precision recycling process is presented using an effective
plate-form positive-electrode in electrochemical machining. It only needs a short period of time to remove the ITO layer easily
and cleanly. 相似文献
94.
Serge Ello Laurence Pirault-Roy Attila Wootsch Zoltán Paál 《Reaction Kinetics and Catalysis Letters》2008,94(2):301-310
Platinum-germanium catalysts supported on a non-acidic Al2O3 have been prepared by adding Ge in amounts corresponding nominally to 1/8 (PtGe1/8/Al2O3); 1/2 (PtGe1/2/Al2O3); 1 (PtGe1/Al2O3) and 2 (PtGe2/Al2O3) monolayers by controlled surface reaction of Ge(n-C4H9)4 to Pt/Al2O3. These catalysts were characterized by electron microscopy (TEM), FTIR of CO adsorption and H2 chemisorption. The ring opening of ethylcyclopentane (ECP) was studied as a test reaction between 543 and 633 K. PtGe1/8/Al2O3 catalyst produced the most ring opening products (ROP) in the whole temperature range. A good agreement with statistical
values of ROP was observed at low temperature, but at higher temperature, the opening became selective, producing mostly heptane.
Bimetallic catalysts PtGe1/Al2O3 and PtGe2/Al2O3 led to a nonselective hydrogenolysis, similar to the monometallic platinum catalyst Pt/Al2O3. The catalysts PtGe1/Al2O3 and PtGe2/Al2O3 produced ROP with the lowest selectivity; instead, much aromatics and fragments were formed, in increasing amounts above
600 K. 相似文献
95.
BAI Yan PAN Xiao-Jing DANG Dong-Bin JIN Ya-Nan WANG Jing-Ping 《结构化学》2008,27(3):311-315
A new Ni(II) complex, [Ni(ftsc)2NO3]NO3 (Hftsc = furan-2-carbaldehyde thiosemicarbazone), has been synthesized and characterized by IR, UV spectra and single-crystal X-ray diffraction analysis. It crystalfizes in a monoclinic system, space group P2 1/n, with a = 10.5203(13), b = 9.2094(11), c = 20.829(3)A,β = 91.518(2)°, V= 2 017.3(5)A^3, Z = 4, F(000) = 1064, Dc = 1.716 g/cm^3, and wR = 0.0800. The complex contains a six-coordinated nickel(II) center which is bound to two imine nitrogen atoms and two thiolato sulfur atoms of two ligands as well as two oxygen atoms from a nitrate anion to assume a distorted octahedral coordination geometry. In addition, intermolecular N-H…O and C-H…O hydrogen bonds between adjacent molecules link the molecules together to form a three-dimensional structure. 相似文献
96.
外消旋大环镍(Ⅱ)配合物[Ni (rac-L)](ClO4)2分别与l-和d-扁桃酸阴离子在乙腈/水溶液中反应,通过手性识别得到六配位的[Ni (RR-L)(S-Man)]ClO4(1)和[Ni (SS-L)(R-Man)]ClO4(2)对映异构体(L=5,5,7,12,12,14-六甲基-1,4,8,11-四氮杂环十四烷,Man=扁桃酸)。当[Ni (rac-L)](ClO4)2与dl-扁桃酸阴离子反应时得到一对对映体等量存在的共聚物,其中大环配体中RR和SS构型分别优先与l-和d-Man- 配位形成外消旋混合物,反应过程中发生了手性识别现象,每颗晶体均为手性对映体。当[Ni (rac-L)](ClO4)2分别与结构类似的dl-2-苯基丙酸和dl-托品酸阴离子反应时,分别得到化合物[Ni (rac-L)(dl-PPA)]ClO4(3)(PPA=2-苯基丙酸)和[Ni (rac-L)(dl-Tro)]ClO4(4)(Tro=托品酸)。X射线单晶衍射结果表明,4个配合物中Ni (Ⅱ)离子均与折叠大环配体L的4个氮原子和2个来自羧基与羟基的氧原子(1和2),或羧基氧原子(3和4)顺式配位,形成六配位八面体构型。配合物1和2属于一对对映异构体,分别通过[Ni (RR-L)(S-Man)]+和[Ni (SS-L)(R-Man)]+分子间氢键作用形成一维之字形链状结构。配合物1和2的单手性特征与圆二色(CD)谱测定结果一致。 相似文献
97.
We introduce a family of solid-state NMR pulse sequences that generalizes the concept of second averaging in the modulation frame and therefore provides a new approach to perform magic angle spinning dipolar recoupling experiments. Here, we focus on two particular recoupling mechanisms-cosine modulated rotary resonance (CMpRR) and cosine modulated recoupling with isotropic chemical shift reintroduction (COMICS). The first technique, CMpRR, is based on a cosine modulation of the rf phase and yields broadband double-quantum (DQ) (13)C recoupling using >70 kHz omega(1,C)/2pi rf field for the spinning frequency omega(r)/2=10-30 kHz and (1)H Larmor frequency omega(0,H)/2pi up to 900 MHz. Importantly, for p>or=5, CMpRR recouples efficiently in the absence of (1)H decoupling. Extension to lower p values (3.5相似文献
98.
采用甘氨酸-硝酸盐(GNP)法合成了新型中温固体氧化物燃料电池(IT.SOFC)的阴极材料Gd1-xSrxCoO3-δ(x=0-0.5)和Gd.0.8Sr0.2Co1-yFeyO3-δ(y=0-1),所合成的初始粉体在800℃下煅烧12 h后均形成了钙钛矿结构的单相固溶体.研究发现,Gd1-xSrxCoO3-δ(GSC)的电导率在600℃时达到了559 S·cm-1,由Ce0.8Cd0.2O2-δ(GDC)电解质和GSC-25GDC材料组成的对称电极在600℃和700℃的界面阻抗分别为0.170Ω·cm2和0.064Ω·cm2,活化能仅为87.8 kJ·mol-1,预示其可以作为ITSOFC较为理想的阴极备选材料;随着Fe3 离子含量的增加,Gd0.8Sr0.2Co1-yFeyO3-δ系列阴极材料的热膨胀系数显著降低,但其电导率也急速下降;此外,通过调整Gd0.8Sr0.2CoO3-δ与GDC的比例可以制备出热膨胀系数与GDC电解质匹配、性能良好的Cd0.8Sr0.2CoO3-δ/GDC复合阴极材料. 相似文献
99.
The application of heavy-metal complexes in bulk-heterojunction (BHJ) solar cells is a promising new research field which has attracted increasing attention, due to their strong spin-orbit coupling for efficient singlet to triplet intersystem crossing. This review article focuses on recent advances of heavy metal complex containing organic and polymer materials as photovoltaic donors in BHJ solar cells. Platinum-acetylide containing oligomersor and polymers have been firstly illustrated due to the good solubility, square planar structure, as well as the fairly strong Pt-Pt interaction. Then the cyclometalated Pt or Ir complex containing conjugated oligomers and polymers are presented in which the triplet organometallic compounds are embedded into the organic/polymer backbone either through cyclometalated main ligand or the auxiliary ligand. Pure triplet small molecular cyclometalated Ir complex are also briefly introduced. Besides the chemical modification, physical doping of cyclometalated heavy metal complexes as additives into the photovoltaic active layers is finally demonstrated. 相似文献
100.