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21.
Sesquialkoxides of Gallium and Indium Treatment of GaMe3 with one equivalent of HOcHex in toluene at 20 °C leads to [Me2GaOcHex]2 ( 4 ) under evolution of methane. The reaction of InMe3 with two equivalents of HOcHex leads under similar conditions not to [MeIn(OcHex)2]n but to the sesquialkoxide [In{Me2In(OcHex)2}3] ( 5 ). 5 can be described also as [{Me2InOcHex)}2{MeIn(OcHex)2}2]. The use of an excess of cyclohexanol in boiling toluene gives the same result. Under these reflux conditions, the reaction of GaMe3 with an excess of PhCH2OH leads exclusively to another type of sequialkoxides, [Ga{MeGa(OCH2Ph)3}3] ( 6 ). 4 — 6 were characterized by NMR, vibrational and MS spectra, as well as by X‐ray structure determinations. According to this, 4 forms centrosymmetrical and therefore planar Ga2O2 four‐membered rings. 5 and 6 possess basically the same structural motif, central M3+ ion ( 5 : In3+; 6 : Ga3+) coordinated by three metalate units ( 5 : [Me2In(OcHex)2]—; 6 : [MeGa(OCH2Ph)3]—). The central M3+ ions have always coordination number (CN) six while the three surrounding metal ions possess CN 4. Because of the spectroscopic findings 6 must exist in two isomers (1:1). The C3‐symmetrical isomer C3‐ 6 was characterized by X‐ray analysis, while the isomer C1‐ 6 could by described mainly by the complex NMR data. 相似文献
22.
Crystal Structures of TMEDA Adducts and of Salts with Protonated TMEDA Molecules The reaction of TMEDA with two equivalents of [BH3(SMe2)] in toluene at 20 °C gives the adduct [TMEDA(BH3)2] ( 1 ). A similar reaction of pyrrolidine with [BH3(SMe2)] in a molar ratio of 1:1 leads to the adduct [pyrrolidine(BH3)] ( 2 ). TMEDA can be introduced into the coordination sphere of In3+ by the treatment of InI3 with TMEDA in toluene to give the complex [InI(TMEDA)] ( 3 ). The salt [HTMEDA]I ( 4 ), containing a mono‐protonated TMEDA molecule, is the result of the reprotonation of [NH4]I and TMEDA in toluene at 20 °C. The salts [H2TMEDA]—[InCl4(TMEDA)]2 ( 5 ) and [H2TMEDA][InCl5(THF)] ( 6 ) are formed in the reaction mixtures TMEDA/toluene/InCl3/HCl and TMEDA/toluene/THF/InCl3/HCl, respectively, whereupon 6 was characterized more closely. Crystals of [In5I6(OH)(TMEDA)4]I·2, 5toluene ( 7 ·2.5toluene) can be obtained after treatment of InI3 with non‐dried TMEDA; 4 was identifed as by‐product. 1 — 7 ·2.5toluene were partially investigated by NMR methods and vibrational spectroscopy. In all cases a characterization by single crystal X‐ray diffraction was performed. According to this, all nitrogen atoms in 1 and 2 are coordinated by BH3 groups leading to a distorted tetrahedral environment at the nitrogen and the boron atoms. In 3 a distorted trigonal‐bipyramidal coordination sphere at the In3+ is present. The apical positions are occupied by I3 and N3. Strong N‐H···N bridges, running along [001] is the feature in 4 ; the I—‐Ions are not involved into the system of H‐bridges. A ion triple, [H2TMEDA][InCl4(TMEDA)]2, hold together by bifurcated H‐bridges is the dominating structural motif in 5 , whereas alternation bifurcated and linear H‐bridges, leading zu a zig‐zag chain along [100], is the build‐up principle of 6 . In 7 ·2.5toluene a complex In5O8 skeleton was formed, consisting of a virtual corner‐connected doubled heterocubane. At every heterocubane a corner, occupied by a metal ion, is missing. The coordination spheres of the In atoms of the complex cation are completed by TMEDA molecules and iodide ions. 相似文献
23.
The alkalimetal phosphoraneiminates [KNPCy3]4, ( 1 ) [KNPCy3]4·2OPCy3 ( 2 ) and [CsNPCy3]4·4OPCy3 ( 3 ) (Cy = cyclohexyl) which are obtainable by the reaction of pottassium amide or cesium amide with Cy3PI2 or Cy3PBr2 in liquid ammonia, as well as the lithium derivative [Li4(NPPh3)(OSiMe2NPPh3)3(DME)] ( 4 ) have been characterized by crystal structure determinations. 4 has been formed by the insertion reaction of silicon greaze (‐OSiMe2)n into the LiN bonds of [LiNPPh3]6 in DME solution (DME = 1, 2‐dimethoxyethane). 1 : Space group P&1macr;, Z = 2, lattice dimensions at 193 K: a = 1389.8(1); b = 1408.1(1); c = 2205.2(2) pm; α = 78.952(10)?; β = 81.215(10)?; γ = 66.232(8)?; R1 = 0.0418. 2 : Space group Pbcn, Z = 4, lattice constants at 193 K: a = 2943.6(2); b = 2048.2(1); c = 1893.8(1) pm; R1 = 0.0428. 3 : Space group Cmc21, Z = 4, lattice dimensions at 193 K: a = 2881.6(2); b = 2990.2(2); c = 1883.7(2) pm; R1 = 0.0586. 4 ·1/2DME: Space group R&3macr;c, Z = 12, lattice dimensions at 193 K: a = b = 1583.5(1); c = 11755.3(5) pm; R1 = 0.0495. All complexes have heterocubane structures. In 1‐3 they are formed by four alkali metal atoms and by the nitrogen atoms of the (μ3‐NPCy3‐) groups, whereas 4 forms a "heteroleptic" Li4NO3 heterocubane. 相似文献
24.
Shahabi Nejad Mohaddeseh Seyedi Neda Sheibani Hassan Behzadi Soheila 《Molecular diversity》2019,23(3):527-539
Molecular Diversity - A new magnetically recoverable silica-based nickel(II) nanocatalyst was synthesized by a simple cost-effective procedure, which was characterized by TEM, SEM, XRD, VSM... 相似文献
25.
Parisa Maboodi Soheila Hemmatzadeh Seyyed Hossein Asadpour H. Rahimpour Soleimani 《理论物理通讯》2014,62(6):864-870
The behavior of the Goos-Hänchen (GH) shifts of the reflected and transmitted probe light beams is theoretically investigated. In a fixed geometrical configuration, the effect of quantum interference induced by spontaneous emission on the phase control of the GH shifts is analyzed in this paper. It is found that in a four-level N-type atomic system as an intracavity medium, the GH shifts of the reflected and transmitted probe light beam are completely phase dependent. 相似文献
26.
Nef‐Isocyanide ‐Based One‐pot Two‐step Three Component Dihydrobenzo[4,5]Imidazo[2,1‐b]thiazoles Synthesis
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Peiman Mirzaei Tayebeh Amanpour Soheila Naderi Ali Abolhasani Soorki 《Journal of heterocyclic chemistry》2016,53(6):1783-1786
The reactive imidoyl chloride adducts generated in situ from the reaction of isocyanide and acyl chlorides were trapped by 2‐mercaptobenzimidazoles to yield highly functionalized dihydrobenzo[4,5]imidazo[2,1‐b]thiazoles in good yields. 相似文献
27.
We report that the amphiphilic natural product, monoacylglycerol 1, functions as a transmembrane Cl(-)/NO(3)(-) anion transporter. The 1,2-diol group is crucial for the transport function since diacylglycerol and triacylglycerol analogs are not anion transporters. Furthermore, adding another hydrogen bond donor to the glycerol head-group and perfluorination of the acyl tail gave synthetic analogs with improved Cl(-) membrane transport properties. 相似文献
28.
An ultra-preconcentration technique composed of solid-phase extraction (SPE) and dispersive liquid–liquid microextraction (DLLME) coupled with gas chromatography–flame photometric detection (GC–FPD) was used for determination of thirteen organophosphorus pesticides (OPPs) including phorate, diazinon, disolfotane, methyl parathion, sumithion, chlorpyrifos, malathion, fenthion, profenphose, ethion, phosalone, azinphose-methyl and co-ral in aqueous samples. The analytes were collected from large volumes of aqueous solutions (100 mL) into 100 mg of a SPE C18 sorbent. The effective variables of SPE including type and volume of elution solvent, volume and flow rate of sample solution, and salt concentration were investigated and optimized. Acetone was selected as eluent in SPE and disperser solvent in DLLME and chlorobenzene was used as extraction solvent. Under the optimal conditions, the enrichment factors were between 15,160 and 21,000 and extraction recoveries were 75.8–105.0%. The linear range was 1–10,000 ng L?1 and limits of detection (LODs) were between 0.2 and 1.5 ng L?1. The relative standard deviations (RSDs) for 50 ng L?1 of OPPs in water with and without an internal standard, were in the range of 1.4–7.9% (n = 5) and 4.0–11.6%, respectively. The relative recoveries of OPPs from well and farm water sat spiking levels of 25 and 250 ng L?1 were 88–109%. 相似文献
29.
Under mild‐ and solvent‐free conditions, one‐pot preparation of 14‐alkyl‐ or 14‐aryl‐14‐H‐dibenzo[a,j]xanthenes could proceed in the presence of catalytic amounts of dodecylphosphonic acid (DPA) and dodecylsulfamic acid (DSA) in good to excellent yields. In these reactions, DPA and DSA are recovered by straightforward work‐ups. 相似文献
30.
The aerobic oxidation of cyclohexene is of great significance from the viewpoints of both fundamental and industry studies as it can transfer the petrochemical feedstock into valuable chemicals. In this research, gold nanoparticles were synthesized on the multi‐layer functionalized reduced graphene oxide . The surface of reduced graphene oxide (rGO) was modified with hydrophobic and hydrophilic layers to create the rGO with scattered hydrophilic positions. The gold nanoparticles were synthesized and immobilized simultaneously in small hydrophilic micro reactors in a mild condition. Characterization of synthesized nanocatalyst was confirmed with different techniques such as TEM, XRD, FT‐IR, and SEM. TEM images of synthesized catalyst show the gold nanoparticles have diameters less than 5 nm. Designed nanonanocatalyst was investigated for the selective liquid phase oxidation of cyclohexene with molecular oxygen in solvent free condition which after optimized conditions a maximum of 88% conversion and 91% selectivity was obtained. 相似文献