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31.
一种合成2-硝亚胺基-5-硝基-六氢化-1,3,5-三嗪(NNHT)的新方法 总被引:2,自引:0,他引:2
主要研究了合成2-硝亚胺基-5-硝基-六氢化-1,3,5一三嗪(NNHT)的新方法.该方法以硝基胍、乌洛托品、浓盐酸为原料,第一步通过成环反应生成中间产物NIHT·HCI,第二步通过硝化中间产物生成目标产物NNHT;中间产物的收率可达到78.3%,目标产物的总收率可达到64.3%以上.同时对影响反应的各种因素进行了分析讨论,如反应温度、反应时间、硝化条件等.利用傅立叶变换红外光%(FT-IR),氢核磁(1H NMR)、碳核磁(13C NMR)、高效液相色谱(HPLC)、元素分析等方法对目标产物进行了表征,确定为目标产物. 相似文献
32.
A. D. Vasiliev A. M. Astakhov M. S. Molokeev L. A. Kruglyakova A. M. Sirotinin R. S. Stepanov 《Journal of Structural Chemistry》2004,45(2):360-364
The structure of 5-nitraminotetrazole lithium salt monohydrate was determined by X-ray diffraction analysis. Crystals are monoclinic, space group P21/c; a = 8.3789(5), b = 10.1872(6), c = 6.6709(5) ; = 106.63(1)°; V = 545.60(98) 3; Z = 4; calc = 1.875 g/cm3. The anion has a planar nitrimine structure with a delocalized negative charge. Each lithium cation (c.n. 5) is bound to three anions and two hydration water molecules. Both oxygen atoms of the nitro groups and the N(3) atom of the tetrazole ring are involved in cation coordination. The geometrical characteristics of the anion are similar to those found for other monosalts of 5-nitraminotetrazole. 相似文献
33.
Yanqiang Zhang Dr. Haixiang Gao Dr. Yong Guo Young‐Hyuk Joo Jean'ne M. Shreeve Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(10):3114-3120
N,N‐Dimethylhydrazinium dicyanamide and nitrocyanamide ionic liquids (ILs) were prepared by quaterization of N,N‐dimethylhydrazine with alkyl halides followed by metathesis reactions with silver dicyanamide or silver nitrocyanamide. The key physicochemical properties, such as melting point and decomposition temperatures, density, viscosity, heat of formation, detonation pressure and velocity, and specific impulse were measured/calculated. The impact of anions and alkyl‐substituted cations on these properties is demonstrated. Droplet tests with white‐fuming nitric acid (WFNA) as an oxidizer were utilized to show that the 14 new N,N‐dimethylhydrazinium salts are hypergolic with ignition delay (ID) times ranging from 22 to 1642 ms, thereby suggesting that some may have potential as bipropellants. 相似文献
34.
35.
Young‐Hyuk Joo Dr. Jean'ne M. Shreeve Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(13):3198-3203
High energy density materials with ethylene‐ and propylene bis(5‐nitroiminotetrazolate) as the anions are reported; all salts were fully characterized by IR, and 1H, 13C, and 15N NMR spectroscopy as well as elemental analyses. In addition, the heats of formation (ΔHf) and the detonation pressures (P) and velocities (D) were calculated.
36.
David B. Cordes Dr. Marcin Smiglak Dr. C. Corey Hines Nicholas J. Bridges Dr. Meghna Dilip Dr. Geetha Srinivasan Dr. Andreas Metlen Dr. Robin D. Rogers Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(48):13441-13448
New, potentially green, and efficient synthetic routes for the remediation and/or re‐use of perchlorate‐based energetic materials have been developed. Four simple organic imidazolium‐ and phosphonium‐based perchlorate salts/ionic liquids have been synthesized by simple, inexpensive, and nonhazardous methods, using ammonium perchlorate as the perchlorate source. By appropriate choice of the cation, perchlorate can be incorporated into an ionic liquid which serves as its own electrolyte for the electrochemical reduction of the perchlorate anion, allowing for the regeneration of the chloride‐based parent ionic liquid. The electrochemical degradation of the hazardous perchlorate ion and its conversion to harmless chloride during electrolysis was studied using IR and 35Cl NMR spectroscopies. 相似文献
37.
38.
The reaction of bis(1,2,4-triazolyl-4-yl) (btr) and MnClO4·6H2O gave rise to a Mn(Ⅱ) complex comprised of unprecedented dinuclear Mn(Ⅱ) units, {[Mn2(btr)3(H2O)5]-(ClO4)4(H2O)2]n(1). Single-crystal X-ray diffraction analysis revealed that 1 crystallizes in the monoclinic space group C2/c. btr adopts two types of bridging modes. One serves as a μ-N1:N2 bridge through one triazolyl ring of btr forming a dinuclear Mn(Ⅱ) unit, and the other adopts an exo-bidentate mode using two nitrogen atoms from each triazolyl ring and links the dinuclear units into a 2D cationic layer. ClO4- acts as a counter anion and does not take part in coordination. Interestingly, 2D layers are packed in an ABCABC mode. ClO4- and uncoordinated water molecules locate between the adjacent layers, and extensive hydrogen bonds further stabilize the whole framework. 相似文献
39.
作者使用计算机绘制了气体分子能量分布曲线图 ,较全面的阐明了活化能与温度的关系。是对无机化学中活化能与温度关系图的改进与补充。 相似文献
40.
采用双十八烷基-L-苯丙氨酸(Bis18-L-Phe)为凝胶因子,制备了具有热可逆性的十四酸异丙酯(IPM)超分子凝胶。IPM凝胶相转变温度(Tgel)随Bis18-L-Phe浓度增大而增加。偏光显微镜(POM)显示在整个IPM凝胶中形成了相互缠绕的针状聚集体。FT-IR光谱分析表明Bis18-L-Phe分子间酰胺的氢键作用是IPM凝胶形成的一个重要驱动力。IPM凝胶动力学研究表明凝胶时间随Bis18-L-Phe浓度的增大而缩短,随着温度升高而延长,因此IPM凝胶时间可以通过温度和Bis18-L-Phe浓度调控。 相似文献