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1.
The possibility of the quantitative determination of water in organic solvents containing strong acids by IR spectrophotometry at 3500–3700 cm?1 was studied. The molar absorption coefficients at the maximum of the most intense absorption bands of water in acetonitrile, chloroform, and 1,2-dichloroethane were 115, 43, and 88 M?1 cm?1, respectively. The study of the effect of acid additions to acetonitrile showed that hydrochloric and nitric acids had little on the shape and intensity of the IR spectra of water. The presence of perchloric acid reduces the intensity (for 0.027 M HClO4, by 40% at 3618 cm?1), which was due to the state of acids in the solvents. Conductometric measurements showed that, under these conditions, HCl and HNO3 were unionized, while HClO4 dissociated almost completely.  相似文献   

2.
无机添加剂对硝酸铵拒爆性的影响研究   总被引:1,自引:0,他引:1  
考察了无机添加剂对农用硝酸铵拒爆性的影响。结果表明,当硝酸铵中添加3%的无机改性剂GXJ 1和10%的无机改性剂GXJ 2后,其拒爆性能明显增强;改性后的硝酸铵按照工业炸药配方配制成铵油炸药,不能被8号雷管起爆。而且改性后的硝酸铵颗粒强度高,不易粉化、结块和吸潮,具有优良的肥料品质。经济效益分析也表明,改性硝酸铵具有广阔的市场应用前景。通过X射线衍射分析、扫描电子显微镜分析等对改性硝酸铵进行了表征,并对拒爆机理进行了初步探讨。  相似文献   

3.
It was found that various organic compounds and inorganic salts added in small concentrations to aqueous solutions increase the quantum yields of photochemical chain ion-radical reactions of the sulfo group substitution for a halogen in halogenated naphthylamine (4-chloro-1 -naphthylamine) and hydroxynaphthalenes (1-bromo-2-hydroxynaphthalene and 4-chloro-2-hydroxynaphthalene). An increase in the quantum yield of the photosubstitution chain reaction of the sulfo group for a halogen on the aromatic ring in the presence of low concentrations of organic compounds and inorganic salts is a phenomenon common to various substrates in both direct and sensitized photolysis. Neither organic compounds nor inorganic salts in low concentrations affect the fluorescence of substrates and the chain length of the substitution reaction. It is suggested that the main effect of small additives on the photochemical chain reaction is due to a change in the reactivity of ionradical pairs, the primary products of a photoinduced electron transfer reaction at the initiation step.  相似文献   

4.
Organic-inorganic polymer composites, consisting of a polyurethane organic phase and a mineral inorganic phase were prepared by the joint polymerization of the urethane oligomer with the water solution sodium silicate. The structure and the morphology of the composites, at a fixed weight fraction of the inorganic component of 20%, and of the corresponding pure polyurethane matrices were investigated by wide-angle and small-angle X-ray scattering (WAXS and SAXS, respectively). The results show similar size (5-7 nm) of the scale of heterogeneity of the composites due to the microphase separation of the rigid and the flexible blocks of the amorphous polyurethane matrix and due to the inorganic crystalline inclusions, i.e. the materials prepared are nanocomposites. The WAXS measurements indicate that the individual properties of the block inorganic component are lost in the nanocomposites, probably due to physical and chemical interactions between the two components. Water sorption from the liquid phase was studied gravimetrically in a composite and in the corresponding polyurethane. The results show high sorption capacity of the composite, due to the hydrophilicity of the inorganic phase and the elasticity of the polyurethane matrix, and allow to estimate the layer thickness of water adsorbed on the inorganic nanoparticle surface to about 20 nm, in reasonable agreement with a model adopted from the literature. WAXS and SAXS measurements on the swelled composite and the swelled-and-dried composite indicate changes in the structure of the inorganic component induced by water, which are, however, to a large extent reversible. These materials may find applications as gel electrolytes and as hydrogels in drug delivery systems.  相似文献   

5.
6.
The effects of plastic additives on depolymerization of polycarbonate (PC) in sub-critical water were examined. Depolymerization of PC with two additives was carried out in an autoclave at temperatures from 533 to 613 K for reaction times ranging from 15 to 60 min. The additives used were a flame retardant (decabromodiphenyl ether, DBDPO) and a plasticizer (di-n-octyl phthalate, DnOP). The main products of PC depolymerization in the presence or absence of the additives were bisphenol A (BPA) and phenol, which were identified by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and gas chromatography mass spectrometry (GC-MS), and quantified by gas chromatography (GC). The addition of DBDPO accelerated the hydrolysis of PC while the addition of DnOP had the opposite effect, and both additives reduced the yield of BPA. The activation energy for PC depolymerization in sub-critical water was found to be lower with DBDPO additive than with DnOP.  相似文献   

7.
In vitro exposure of human lymphocyte cultures to spindle inhibitors reduce the average chromosome length1,2. In this report chromosome length measurements were used for indirect but quantitative evaluation of the effects of inorganic and organic lead compounds on spindle function. The data indicate that organic compounds are much more powerful spindle inhibitors than inorganic lead compounds, almost as potent as colchicine. Occupational exposure to organic lead compounds may result in partial spindle inhibition, leading to a high probability of nondisjunction.  相似文献   

8.
A 50 Hz magnetic field effect on the growth of yeasts Saccharomyces cerevisae was studied. The cylindrical coil induced magnetic fields with inductions up to 10 mT. Duration of exposure varied up to 24 min. Exposure took place at laboratory temperature (24-26 degrees C) and the air ventilator maintained the temperature at the place of the sample. We measured the growth curves of yeasts in broth and we calculated the number of CFU (colony forming units) on solid soil. We found that magnetic field decreases the number of yeasts, and slowed down their growth. The result is similar to the experiments with bacteria E. coli, S. aureus and L. adecarboxylata. It seems that the magnetic fields kill a part of yeasts and the bigger part of them survives and continues in their growth.  相似文献   

9.
Zheng  Xinyan  Hu  Po  Yao  Ruxian  cheng  Jinhe  Chang  Yiheng  Wu  Haitao  Mei  Hongying  Sun  Shuxiang  Chen  Qingtai  liu  Fang  Chen  Shujing  Wen  Hua 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2217-2226
Journal of Radioanalytical and Nuclear Chemistry - Enhancement of U(VI) biomineralization by Saccharomyces cerevisiae through addition of inorganic phosphorus was studied in this work. The addition...  相似文献   

10.
The effects of propionic acid on ethanol and glycerol production by Saccharomyces cerevisiae in cassava mash were examined along with the influence of pH (4.0, 5.0, and 6.0) and of dissolved solids content (22%, 25%, and 27%). Inhibition by propionic acid increased as solids content increased and medium pH declined. Complete inhibition of ethanol fermentation was observed in mashes at pH 4.0 (60 mM propionic acid for 22% solids and 45 mM for 25% and 27%). Glycerol production linearly decreased with increased undissociated propionic acid concentration in all mashes at all pH levels, which partly contributed to increased final ethanol production when propionic acid concentration in mashes was low (≤ 30 mM).  相似文献   

11.
The solar cell surface morphologies with different additives observed with slightly changed in roughness. It is easily to get the best PCE of 11.1% with using 0.5% DIO additives.  相似文献   

12.
Monitoring of trace impurities in electroplating bath is needed to meet EU requirements for WEEE and RoHS and for quality control of electrodeposits. Methods using IC and 100% aqueous CE buffer were found producing non-repeatable results attributed to interference of surfactants and major methanesulphonate anion. A new CE buffer containing 1.5 mM tetraethylenepentaamine, 3 mM 1,3,5-benzenetricarboxylic acid and 15 mM Tris in 20% (v/v) methanol at pH = 8.4 was shown to enhance the separation window, reduce interaction between buffer and bath constituents, and give satisfactory repeatability with baseline separation for 14 organic and inorganic anions within 14 min, good repeatability for migration time (0.32–0.57% RSD), satisfactory peak area and peak height (2.9–4.5 and 3–4.7% respectively), low detection limit (S/N = 2, 20–150 ppb), and wide working ranges (0.1–100 ppm). The CE buffer with 20% (v/v) methanol has demonstrated its capability for identifying anion impurities causing problem in aged tin bath and the use of only 10-fold dilution to produce reliable results for quality assessment in plating bath containing high surfactant additives.  相似文献   

13.
Hui Sun  Benxian Shen 《Adsorption》2012,18(2):103-111
The crystallization of zeolite A was monitored by measuring the adsorption capacities of synthetic products. The influences of organic additives on the crystallization process and adsorption performances of zeolite were investigated. SDS (sodium dodecyl sulphonate), TWEEN (Tween-80), and PEG (poly(ethylene glycol)) shorten the induction period by reducing the interfacial energy while SCMC (sodium carboxymethylcellulose) can prolong the induction period by increasing the interfacial energy. TEA (triethanolamine) can also suppress the nucleation through reducing the effective supply of aluminum. All the organic additives but SCMC diminish the rate of crystal growth. CTAB (cetyltrimethylammonium bromide) causes the destruction of crystal structure and reduce the concentration of OH? ions. As a result, the rate of crystal growth is significantly reduced. Meanwhile, PAM (poly(acrylamide)), SDS, TWEEN, HMTA (hexamethylenetetramine), and PEG increase the viscosities of synthesis systems, thus, diminish the growth rate. PAM restrains the transformation of zeolite A crystal into hydroxysodalite one, therefore, tremendously improves the stability of crystals of zeolite A. In addition, PAM can promote the rates of n-hexane adsorption on zeolite 5A because of the impact of PAM on the crystal-size distributions of zeolite 5A.  相似文献   

14.
The results of long-term researches of thin films prepared from tetraethoxysilane-derived sols containing inorganic and organic additives are systematized and analyzed. These additives give to films certain physicochemical properties for their application in electronic techniques, optics, power engineering, in biological technologies etc. The influence both inorganic (salts, acids) and organic (polyols, polyionenes, epoxy resin) additives on rheological properties and aggregate stability of sols as well as films surface morphology is minutely considered. The explanations of phenomena during film formation, including spin-coating process, are given. Essential influence of temperature and humidity on films surface morphology is shown. Influence of heat treatment modes on structure and composition of films is analyzed. Recommendations about optimization of thin films sol–gel processing are offered.  相似文献   

15.
16.
17.
Yao L  Liu Q  Li Y  Yao S 《Journal of separation science》2011,34(18):2441-2447
Separation of inorganic anions by capillary electrophoresis (CE) is usually conducted in co-electroosmotic mode due to the large electrophoretic mobilities of inorganic anions. Semipermanent surfactant coatings have been shown to be effective for CE of inorganic anions due to their strong capability of electroosmotic flow (EOF) manipulation. However, semipermanent coatings often suffer from their unsatisfactory stability. In addition, organic solvent additives are usually required to adjust the selectivity, which also aggravate the degradation of coating. In this work, a novel semipermanent coating consisting of cationic Gemini surfactant 18-10-18 and nonionic surfactant Tween 20 was developed to separate inorganic anions in CE. This coating is easy to prepare and more stable than pure Gemini coating. The introduction of nonionic surfactant in the coating not only suppresses the reversed EOF but can also adjust the selectivity of separation. Good separations of six model anions were achieved, the separation efficiency was as high as 65040-169700 plates/m and the RSDs of the migration times were less than 0.5 and 2.5% for run-to-run and day-to-day assays, respectively. Calibration curves were linear in the range of 0.05-5.0 mM; the detection limits ranged from 20 to 50 μM. More importantly, no organic solvents are required in the background buffer to achieve the satisfactory separations. This guarantees the coating stability and makes the method greener than most of other methods for CE of inorganic anions.  相似文献   

18.
The preconcentration and separation of copper, cadmium, cobalt and nickel 8-quinolinolates in solutions of high salinity including synthetic sea water is studied with phenolphthalein or 2-naphthol as collector and octadecylamine as surfactant. A simplex optimization is applied. Yields > 90% are achieved for Ni, Co and Cd with both collectors, but the copper yield is low. Flame atomic absorption spectrometry is used for the final measurements.  相似文献   

19.
Processing additives are used in organic photovoltaic systems to optimize the active layer film morphology. However, the actual mechanism is not well understood. Using X-ray scattering techniques, we analyze the effects of an additive diiodooctane (DIO) on the aggregation of a high-efficiency donor polymer PTB7 and an acceptor molecule PC(71)BM under solar cell processing conditions. We conclude that DIO selectively dissolves PC(71)BM aggregates, allowing their intercalation into PTB7 domains, thereby optimizing both the domain size and the PTB7-PC(71)BM interface.  相似文献   

20.
The deliquescence behavior of ternary inorganic (ammonium sulfate and ammonium nitrate)/organic (glutaric acid and malonic acid)/water aerosol particles has been investigated at 293 K using a novel surface aerosol microscopy (SAM) technique. The results obtained for the deliquescence relative humidities (DRH) for particles of variable inorganic/organic contents show a eutectic behavior with the mixed particles showing deliquescence at lower DRH compared to the pure inorganic and organic components, respectively. This behavior has been quantitatively modeled using the extended aerosol inorganics (E-AIM) thermodynamic model of Clegg et al. in combination with the UNIFAC group activity approach to account for organic molecular solutes. In addition, we have investigated the crystallization behavior of supersatured and formerly deliquesced ternary solution droplets using space resolved Raman spectroscopy. It is found that such droplets produce solid particles in which the inorganic and organic phases show some spatial separation with the organic component being predominantly found at the outer part of the particle. Independent measurements of the contact angles of such ternary droplets reveal that their angles are within experimental error identical to those of the purely organic/water solutions.  相似文献   

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