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81.
The dielectric relaxation spectroscopy (DRS) of Winsor I -Ⅲ microemulsions for nonionic surfactant octyl polyglucoside CsG1.46/1-butanol/cyclohexanedwater system was studied. The experiment shows that the permittivity decreases with the increase in the frequency and clear dielectric relaxation phenomena were observed. Permittivity obviously decreases with the change of the microstructure of the microemulsion, W/O, B.C. and O/W can be distinguished by the permittivity.  相似文献   
82.
本实验采用金属有机化学方法成功地将富勒烯分子引入到PNVC侧链形成CBP(CharmBraceletPolymer)型共聚功能材料,研究了其UV-VIs谱行为。结果表明,C_(60)或C_(60)/C_(70)混合物化学修饰的产物其紫外可见谱明显向长波方向移动,谱峰范围由280nm扩展至870nm。C_(60)含量增加,红移程度增大,在可见区域的吸收程度亦增加。产物主要存在5个特征峰,分别位于215nm、265nm、298nm、335nm、345nm处,其中215nm峰为C_(60)仅存的特征峰。最后讨论了不同合成条件与产物硝化处理对其UV-VIS谱行为的影响。  相似文献   
83.
An efficient solution-processable route employing Pb(Ac)2 as lead source and anti-solvent treatment to achieve fully covered and homogenous perovskite films is reported.  相似文献   
84.
动态法测定耐硫甲烷化催化剂的有效导热系数   总被引:1,自引:2,他引:1  
本文采用动态法原理,用单丝直径为0.2mm的铜-录铜热偶作为测温元件,在313-533K温度区间,测定了耐硫甲烷化催化剂的有地热系数。用石蜡和锡作为参比物,对所用仪器及实验方法进行了可靠性检验。实验表明,动态法是测定多孔硫化物催化剂导热系数的有效方法。其精度符合工程要求,亦能用于其它材料导热系数的测定。对所测数据用单纯形方法优化拟合,得到大于353K范围内的有效导热系数的经验公式。  相似文献   
85.
The electrocatalytic properties of the SiC particle‐modified glassy carbon electrode (MGC) for adrenaline oxidation were studied by cyclic voltammetry (CV), double‐potential step chronocoulometry (DPSCC), and electrochemical impedance spectroscopy (EIS) techniques in McIlvaine buffer solution. It was shown that the electrode modified with SiC particles markedly displayed an electrocatalytic effect on the process of the electrochemical reaction of adrenaline, i.e., the activity and the reversibility of the MGC electrode has been significantly improved. This was attributed to the adsorption effect of the electroactive adrenaline molecules on the MGC electrode surface.  相似文献   
86.
用时间分辨-傅立叶变换红外发射光谱法研究了OH自由基与CO的反应.OH自由基由248 nm的激光光解硝酸得到.在实验中首次观测到了产物CO2的非对称伸缩振动(ν3)的激发态.对CO2发射光谱的拟合结果显示,其振动态的布居在量子数v=2时最大 ,而最高振动量子数达到v=6.由实验得到的CO2振动布居与Schatz等人用全量子化计算该反应的中间物HOCO解离动力学得到的CO2布居结果能很好地吻合.  相似文献   
87.
An ultrathin, ordered, and packed protein film, consisting of the 2-mercaptoacetic acid (MAA), polydimethyldiallylammonium chloride (PDDA), and wild-type (WT) photosynthetic reaction center (RC; termed as WT-RC) or its pheophytin (Phe)-replaced counterpart (termed as Phe-RC), was fabricated by self-assembling technique onto gold electrode for facilitating the electron transfer (ET) between RC and the electrode surface. Near-infrared (NIR)-visible (Vis) absorption and fluorescence (FL) emission spectra revealed the influence of pigment substitution on the cofactors arrangement and excitation relaxation of the proteins, respectively. Square wave voltammetry (SWV) and photoelectric tests were employed to systematically address the differences between the WT-RC films and mutant ones on the direct and photo-induced ET. The electrochemical results demonstrated that ET initiated by the oxidation of the primary donor (P) was obviously slowed down, and the formed P+ had more population as well as more positive redox potential in the Phe-RC films compared with those in the WT ones. The photoelectrochemical results displayed the dramatically enhanced photoelectric performances of the mutant ones, further suggesting the slow-down formation of final charge-separated state in Phe-RC. The functionalized protein films introduced in this paper provided an efficient approach to sensitively probe the redox cofactors and ET differences resulting from only minor changes in pigment arrangement in the pigment–protein complex. The favored ET process observed for the membrane proteins RC was potentially valuable for a deep understanding of the multi-step biological ET process and development of versatile bioelectronic devices.  相似文献   
88.
A potential-derived atomic multipole method called the cumulative potential-derived atomic multipole method is developed, with which electrostatic atomic multipole moments are derived by fitting the molecular electric potential in a cumulative way. It is applied to the hydrides of N , O , F , S , Cl , and methanol and the hydrogen-bonded dimers formed between them. The relationship between atomic multipole moments and molecular charge distributions is found. The structures calculated with Buckingham's electrostatic model are in good agreement with experiments. The phenomena of nonlinear structures of most H -bonded complexes—the deviations of symmetry axes of electron donors from H bonds—and correct distinguishing between two alternative structures are attributed to atomic dipole and quadrupole moments. Compared with other methods, this method has a quantitative and qualitative advantage and simple algorithm. The main conclusion is that the atomic multipole moments play a substantial role, although a potential-derived charge model was deemed sufficient previously. © 1993 John Wiley & Sons, Inc.  相似文献   
89.
结合膜的形态结构研究了以 LiCl为添加剂制得的疏水 PVDF膜的膜蒸馏性能。与来用水溶液高分子添加剂制得的PVDF微孔膜相比,膜蒸馏性能有了较大提高,尤其具有更高的截留率。制得的微孔膜的蒸馏通量已接近商品膜的膜蒸馏通量,表明以LiCl为添加剂制得的PVDF疏水微孔膜是一种适用于膜蒸馏的较理想的疏水微孔膜。  相似文献   
90.
用三原子模型的准经典轨线方法研究了Cl与C2H6(v=0,j)的反应。计算结果表明,反应产物HCl的角度分布基本上为各向同性,其振动分布处于基态,与实验结果相一致。对反应轨线的研究表明,该反应为一直接反应,而且反应碰撞在低及高的碰撞参数下的机理不一样,在低碰撞参数下反应碰撞是直接完成的,产物HCl以向后散射为主,转动基本上是冷的,但比高碰撞参数下的热。在高的碰撞参数下则生成短寿命的碰撞复合物,产物  相似文献   
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