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排序方式: 共有173条查询结果,搜索用时 15 毫秒
1.
The synthesis of chiral oxazolidinedione derived bicalutamide analogs has been discussed. 相似文献
2.
Ram Parkash S. C. Ahluwalia S. C. Sud R. N. Sahni R. C. Paul 《Monatshefte für Chemie / Chemical Monthly》1981,112(6-7):707-711
Heats solution of someLewis acids and bases in acetic anhydride have been determined and the following order of their relative strengths is proposed: SbCl5>SO3>SnCl4>TiCl4>AsCl3 and piperidine>
n-butylamine>potassium acetate>sodium acetate -picoline>quinoline. Heats neutralization of theseLewis acids and bases in acetic anhydride suggest that the major enthalpy change in these neutralization reactions is due to the combination of a proton and the (CH2COOCOCH3)-ion, resulting in the formation of acetic anhydride.
Lösungs- und Neutralisationswärmen von Lewis-Säuren und-Basen in Essigsäureanhydrid
Zusammenfassung Es wurden die Lösungswärmen einigerLewis-Säuren in Essigsäureanhydrid bestimmt und folgende Reihung nach ihrer relativen Stärke vorgeschlagen: SbCl5>SO3>SnCl4>TiCl4>AsCl3 und Piperidin> n-Butylamin>KAc>NaAc-Picolin>Chinolin. Die Neutralisationswärmen dieserLewis-Säuren und-Basen legen nahe, daß der Hauptanteil daran auf die Reaktion eines Protons mit (CH2–COOCOCH3)-zurückzuführen ist.相似文献
3.
C.N.R. Rao Om Parkash D. Bahadur P. Ganguly S. Nagabhushana 《Journal of solid state chemistry》1977,22(3):353-360
Electronic and magnetic properties of Ln1?xSrxCoO3 (Ln = Pr, Nd, Sm, Eu, and Gd) systems show that above a critical value of x, the d electrons become itinerant while the materials become ferromagnetic at low temperatures. The ferromagnetic component increases with increase in x and decrease in temperature. The Curie temperature increases with x and decreases with decrease in the size of the rare-earth ion. Incorporation of Ba2+ in LaCoO3 favors itinerant electron ferromagnetism relative to Sr2+ while Ca2+ is less favorable than Sr2+. 相似文献
4.
5.
Bromine cyanide has been used for the potentiometric determination of sulphide, sulphite, thiocyanate, iodide, tin(II), arsenic(III),hydrazine hydrate, phenylhydrazine, 1,1-methylphenyldrazine and chloralhydrazine in glacial acetic acid and 1 : 1 acetic acid-acetic anhydride mixture, of thiourea, ethylthiourea, isopropylthiourea, benzylthiourea, alpha-phenylthiourea and o-tolythiourea in methanol, and of sodium methyl-, ethyl-,dimethyl-, diehtyl- and isopropyldithiocarbamates in ehtanol and acetonitrile media. The behaviour of bromine cyanide in these non- aqueous solvents has been compared with its behaviour in aqueous medium and with that of iodine cyanide in these non-aqueous solvents. 相似文献
6.
A sensitive and inexpensive method of spectrophotometric determination of chromium(VI), based on the absorbance of its complex with malachite green and acetic acid at pH 2.5 is reported. The complex shows a molar absorptivity of 8 x 10(4) l.mole(-1) cm(-1) at 560 nm, using malachite green and acetic acid as reference solution. The effect of time, temperature, pH and reagent concentration is studied and optimum operating conditions are established. Beer's law is applicable in the concentration range 2.0-22.8 mug/ml chromium(VI). The resin beads act as a catalyst and as little as 1.6 mug of chromium(VI) is detected in the resin phase as compared to 4.1 mug in the solution phase. The standard deviation in the determinations is +/-0.40 mug/ml for a 10.35 mug/ml solution. 相似文献
7.
Anand Kumar Chaudhari Vipin Kumar Singh Abhishek Kumar Dwivedy Somenath Das Neha Upadhyay Akanksha Singh 《Natural product research》2020,34(5):745-749
AbstractThe chemical characterisation of Pimenta dioica essential oil (PDEO) revealed the presence of 50 components, amongst which α-Terpineol (30.31%) was the major component followed by β-Linalool (6.75%) and γ-Terpinene (4.64%). The oil completely inhibited the growth of aflatoxin B1 secreting strain Aspergillus flavus LHP-VS-8 and aflatoxin B1 production at 2.5?µL/mL and 1.5?µL/mL, respectively. The oil caused dose dependent reduction of methylglyoxal (an AFB1 inducer), enhanced leakage of Ca2+, Mg2+ and K+ ions and significantly reduced ergosterol content of fungal plasma membrane. During in situ experiments, PDEO exhibited complete protection of fumigated maize cob slices from fungal infestation without affecting seed germination. The chemically characterised PDEO is recommended as a plant based preservative and shelf life enhancer of food commodities by preventing fungal growth, AFB1 production and lipid peroxidation. This is the first report on PDEO as inhibitor of AFB1 secretion and methylglyoxal biosynthesis. 相似文献
8.
Cyriac Vipin Ismayil Noor I. M. Mishra Kuldeep Chavan Chetan Bhajantri Rajashekhar F. Masti Saraswati P. 《Cellulose (London, England)》2022,29(6):3271-3291
Cellulose - In this paper, we report the effect of doping sodium iodide (NaI) salt into a polymer blend matrix of sodium carboxymethyl cellulose (NaCMC) and poly(vinyl alcohol) (PVA). Solution... 相似文献
9.
Vipin Amoli Rashmi Tiwari Arghya Dutta Prof. Asim Bhaumik Dr. Anil Kumar Sinha 《Chemphyschem》2014,15(1):187-194
Structurally thermostable mesoporous anatase TiO2 (m‐TiO2) nanoparticles, uniquely decorated with atomically dispersed SiO2, is reported for the first time. The inorganic Si portion of the novel organosilane template, used as a mesopores‐directing agent, is found to be incorporated in the pore walls of the titania aggregates, mainly as isolated sites. This is evident by transmission electron microscopy and high‐angle annular dark field scanning transmission electron microscopy, combined with electron dispersive X‐ray spectroscopy. This type of unique structure provides exceptional stability to this new material against thermal collapse of the mesoporous structure, which is reflected in its high surface area (the highest known for anatase titania), even after high‐temperature (550 °C) calcination. Control of crystallite size, pore diameter, and surface area is achieved by varying the molar ratios of the titanium precursor and the template during synthesis. These mesoporous materials retain their porosity and high surface area after template removal and further NaOH/HCl treatment to remove silica. We investigate their performance for dye‐sensitized solar cells (DSSCs) with bilayer TiO2 electrodes, which are prepared by applying a coating of m‐TiO2 onto a commercial titania (P25) film. The high surface area of the upper mesoporous layer in the P25–m‐TiO2 DSSC significantly increases the dye loading ability of the photoanode. The photocurrent and fill factor for the DSSC with the bilayer TiO2 electrode are greatly improved. The large increase in photocurrent current (ca. 56 %) in the P25–m‐TiO2 DSSC is believed to play a significant role in achieving a remarkable increase in the photovoltaic efficiency (60 %) of the device, compared to DSSCs with a monolayer of P25 as the electrode. 相似文献
10.
Nonlinear Dynamics - In the present article, a combination of numerical and experimental studies is undertaken to comprehend the influence of noise on the responses of continuous-time dynamical... 相似文献