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1.
This study reports preparation of glass composition (54.50 wt.%) SiO2, (10.80 wt.%) B2O3, (14.20 wt.%) Na2O, (1.20 wt.%) K2O, (6.00 wt.%) CaO, (4.00 wt.%) Fe2O3 and (9.30 wt.%) TiO2 by melt quenching method using direct microwave heating and conventional resistive heating. Study of dielectric loss factor of the glass as function of temperature illustrated increasing loss factor above 370 ℃, 550 ℃, 650 ℃ and 900 ℃, indicating enhanced microwave absorption by the glass at above these temperatures. Chemical analysis results of both the glasses depicted more volatilization loss of volatile ingredients in conventional heating. The study of chemical durability was performed from leachate analysis describing less leaching of Na2O, K2O and other constituents from glass melted in microwave furnace. Glass transition temperatures (Tg) were found to be 576.3 ℃ and 569.5 ℃ for glass melted in conventional and microwave heating route, respectively. Laboratory experiment of glass melting utilizing microwave energy as an alternate heating source demonstrated 70%-75% electrical power saving.  相似文献   

2.
Energy is essential for every human activity for more comfortable life, but it also consumes more natural resources. Fossil fuel is the major energy source for energy consumption, and it also emits a lot of air pollution during usage to atmosphere and not reproductively. Electrical energy is the secondary energy sources from fossil fuel which is used to operate air conditioning system. In order to control human comfort temperature, it is usually required when the temperature differences swing between indoor and outdoor temperatures. PCMs (phase change materials) are the high latent heat materials which can be used in building materials for energy conservation purpose. PCMs can store thermal energy and prevent heat to pass through temperature control areas. Paraffin has been used as PCMs which is absorbed into the pore of fly ash as paraffin/fly-ash composite and mixed into the buildings materials. Paraffin is an organic material with high melting point (-59 ~C) and nonflammable material, therefore, it can be used as the building materials for the function of PCMs for energy saving purposes. Composite PCMs can be prepared by vacuum impregnation process. Paraffin in liquid form will be impregnated into the pore of fly ash by vacuum capillary force to form paraffin/fly ash composite PCMs. Vacuum impregnation pressures, vacuum times, impregnation times of liquid paraffin in fly ash pores and temperatures for melting the solid paraffin into the liquid form are all affect on the thermal properties of paraffin/fly ash composite PCMs. Composite PCMs will be selected by the optimum thermal properties with optimum of the production conditions for replace the cement powder in the mortar plate compositions. Cement mortar plate with and without composite PCMs will be tested for the thermal insulation properties by comparison as the real day and night time for 8 h period from spot light turn on and off. Temperature detection on the surface and inside the model building under mortar plate with and without composite PCMs is detected every 1 min. Temperature differences between surface of mortar plate over the model building and inside temperature of model building under mortar plates increase with more composite PCMs contents in mortar plates. Thermal insulation efficiency in the building can be enhanced by the composite PCMs utilization as the composition of the building materials.  相似文献   

3.
This paper describes technology of the electromagnetic pump made in a hybrid polymer-ceramic technology. The pumping mechanism is realized with a mutual excitation between an electromagnetic coil and a neodymium magnet bonded to a flexible membrane. A PDMS (poly(dimethylsiloxane)) material was used to manufacture a membrane sufficient for the presented micropump. A fish trap construction is adapted to the ceramic technology. The bonding process of ceramics and polymer, using plasma oxidation method, is described as well. Moreover, a membrane deflection depending on magnet dimensions and applied voltage was measured.  相似文献   

4.
This paper presents a study of the relationship between the magnetic properties and microstructure of nanocomposite Ni/MnO, Ni/CoO, Co/MnO, Co/CoO. The objective is to understand how the coupling interface FM/AFM (ferromagnetic/anti-ferromagnetic) manifests itself in magnetic response of these materials to an applied field. Sample preparation was performed using mechanochemical synthesis by means of a ball mill planetary type high power at normal atmosphere. The characterization was done by XRD (X-ray diffraction), SEM (scanning electron microscopy) and VSM (vibrating sample magnetometry). Analyzing the XRD peaks of the samples studied, there was a decrease in the average particle diameter with increasing milling time, which is important in the magnetic interactions of the atoms of the surface. In addition, the diffraction pattern showed formation of new phases by oxidation interfering with the magnetic measurements. Analyses by SEM show chipboard multiform nano- and micrometer-sized grains on the surface of the clusters being responsible for the interaction. The magnetic measurements show a strong coupling between the phases present in nanocomposites showing once again that the MS (mechanosynthesis) is a powerful technique for this kind of purpose. The effect of the decrease in crystallite size leads to large variations of magnetic properties of the material which have been specifically observed changes in HC (coercive field) in the RM (remanent magnetization) and SM (saturation magnetization). The decrease in crystallite size in the course of grinding intensifies the effects that depend on the surface-to-volume ratio of the material. M vs. T measures were taken for different values of applied field and found a jump in the moment of the sample near the N6el temperature of the antiferromagnetic.  相似文献   

5.
It is discovered a new three-, four-component Petasis, Passerini, Hantzsch, Kabachnic-Fields, Ugi reactions with of arsine, stibine and bismuthine in organometallic chemistry. Modifications were replaced to a nitrogen atom of classical reactions of atoms of phosphorus, arsenic, antimony and bismuth. It has been proposed a new mechanism for possible reactions.  相似文献   

6.
The catalytic system is investigated in a computer chromatography. The sorbent represents the nanostructure composite with hardpolymer electrolyt. As the nanostructure polymeric system, it used dendrimer who are absorbed on a surface with formation of monolayer. In chromatography column watch dimensional effect. The size of a particle carries out a role of temperature. In the article, investigate solvatation and dimensional effect reaction self-assembling gas dimmers. Distance critical radius H+ transfer define equation: rcr = 2rs. Reaction accompaniment transfer energy. Transfer energy realize on exchange-resonanse mechanism.  相似文献   

7.
The authenticity of 91 wines produced in Cyprus from both indigenous and other vine varieties were investigated by a holistic approach, using, advanced technology such as SNIF-NMR (site-specific natural isotopic fractionation-nuclear magnetic resonance) and 1R-MS (isotope ratio-mass spectrometry) for the determination of the stable isotopes and ICP (inductively coupled plasma spectroscopy) for some heavy metals. The spectroscopic characteristics were evaluated statistically using different chemometric methods. The dependency of the D/H (deuterium/hydrogen) ratio of the methylene site in the ethanol molecule (D/H)ll and also theδ ^18O values of the wine water, were the most useful discriminators. Isotopic results allow us to have a complete idea about the regional variability of the isotopes. Among the metals, Ni followed by Pb was the ones with the highest discrimination value. The determined concentrations of Pb, Ni, Cr and Cd that are related to the safety of wines were within the acceptable limits that have been established by the OIV (international organization of vine and wine) or comparable with the results of the wines of other European countries. The study of the correlation between the load of heavy metals and isotopes in wines showed a dependence on the grape variety but not the geographical location of the vineyard. This is probably due to the close proximity of wine regions in Cyprus.  相似文献   

8.
Many of the traditional woods used for musical instruments have been selected not only for their natural beauty but for the high content of waxes and resins that help increase water repellency of the wood but have little or no effect on stabilizing dimensions or vibrational properties. Moisture changes have a great negative effect on both the musical quality of wooden musical instruments and limit the length of time they can be played without loss of musical quality. It is possible to stabilize both the wood and the vibrational properties by chemically modifying the wood. One technology that can do this is the reaction of wood with acetic anhydride. Acetylation of wood slightly increases density, and slightly (about 5%) reduces both sound velocity and sound absorption when compared to unreactedwood. Acetylation does not change the acoustic converting efficiency. Acetylation reduces the amount of moisture in the cell wall decreasing the effect of moisture on the viscose properties of wood. This allows a wooded musical instrument to be played longer without having to let it dry out. This gives an instrument made from acetylated wood a greater range of moisture conditions it can be played in without losing tone quality. Acetylation also greatly stabilizes the physical dimensions of the wood. The major effect of acetylation of wood, therefore, is to stabilize acoustic properties. The technology can be applied to almost any wood though more easily to permeable types so non-traditional wood species can be used. A violin, a piano soundboard, a guitar, a recorder, a bagpipe chanter, and trumpet and trombone mouthpieces have been made using acetylated wood with very positive results. Several more wooden instruments made from acetylated wood are presently being made for further testing and early market development.  相似文献   

9.
In this article, we have performed B3LYP/6-31+G(d) calculations of geometrical and reaction enthalpies of antioxidant mechanisms for ADPHT 1-4 (3-alkyl-4-phenylacetylamino-lH-1,2,4-triazol-5-ones) and its derivatives: HAT (hydrogen atom transfer), SET-PT (single electron transfer-proton transfer) and SPLET (sequential proton-loss electron transfer) were investigated in gas and solution-phases. Solvent contribution to enthalpies was computed employing integral equation formalism IEF-PCM (integral equation formalism method) method. It turned out that the lowest BDEs (bond dissociation energies) is obtained for C-H bonds due to captodative effect in various media. Results indicate that HAT mechanism represents the most anticipated process in gas-phase from thermodynamic point of view. But, the SPLET represents the thermodynamically preferred reaction pathway in solvents (2-propanol, acetonitrile, DMF (N,N-dimethylformamide) and water). The authors showed that bond dissociation energies, IP (ionization potential) and PA (proton affinity) are sufficient to evaluate the thermodynamically preferred mechanism.  相似文献   

10.
It was discovered a new approach modification Bart, Beschamp, Mayer, Rosenmund, Scheller, Sherlyn-Braz reactions with of arsine, stibine and bismuthine in organometallic chemistry. The authors have proposed a new mechanism for possible reactions.  相似文献   

11.
Recently, the demand for REEs (rare earth elements) has been heavily increasing, as they are used in many high-tech products (e.g., because of their specific magnetic behavior). As a result, the supply situation for REEs is worsening and the world market is depending on Chinese exports, so that it may be worthwhile to recycle e-waste (electronic waste) in European countries. This article describes an analytical method to analyze REEs in different kinds of e-waste with the help of a simultaneous ICP-OES (ICP optical emission spectrometer). The task is challenging because samples show significant differences in terms of major, minor and trace element concentrations. Depending on the field of application, the level of matrix elements and target elements differs completely, resulting in a wide variety of spectral interferences. The method presented in this article allows an accurate quantification of REEs as well as a high sample throughput. In addition to REEs, other elements of economic interest can be determined in the same way. The development of a sample preparation process is another important issue and considered as well.  相似文献   

12.
Transportation of energy and substances is fundamental for the conditions of life. The energy from metabolised food is yielded at the reduction of oxygen by the assistance of Se-enzymes. Activated Se-enzymes contain an electron conducting Se-link with elemental Se bounded to Se-cys (Se-cystein) that prevents electron transferring (autoxidable) agents, as arginine, from oxidations. NO is formed from e.g. arginine during the passive state of a Se-enzyme. With NO, instead of O2, bounded to a hem group, destroying oxidations are avoided. This is the role of NO. A nerve signal is activated by the GTP (guanosine triphosphate)-induced triggered transformation of cGMP (cyclic guanosine monophosphate) into GMP, closing the sodium channels. When GTP is consumed, the opposite reaction takes place. The direct influence of the GMP/cGMP quote on a nerve signal makes GMP/cGMP equal to EDHF (endothelium-derived hyperpolarizing factor). Part of the energy from food is stored and transported in the form of acetyl groups, building up many important molecules of which LDL (low density lipoprotein) is one, containing cholesteryl esters. These are brought in to the cell, decomposed to acetyl groups generating hydrogen, H, making LDL to an essential substance. High levels are connected to impaired energy yielding reactions, perhaps related to low levels of some substances, especially to one or both forms of Se. The necessity of a Se-link and NO induced protection against oxidations by reducible oxygen can no longer be neglected.  相似文献   

13.
Contamination of the environment by pesticides is the inevitable aftermath of plant protection, and a substantial portion of pesticide pollutants exists in the form of aerosol particles levitated in the air and deposited on plants, and as the pesticide residues (thin films) on the surface of plant leaves. The sunlight photolysis could be the resource for the accelerated photochemical decomposition of pesticide compounds to minimize the long-term environmental contamination. The rates of photochemical decomposition of pesticide chemicals propiconazole (commercial formulation Tilt) and haloxyfop-ethoxyethyl (Zellek) were measured in particles of 0.12-1.3 μm in diameter and in films 0.04-0.2 μm thick. A specific polyaromatic sensitizer Shirvanol was used to induce accelerated decomposition of the above pesticide particulates under both the solar radiation and the artificial UV light. It was established that propiconazole decomposes by the sensitized photo-oxidation only, but haloxyfop-ethoxyethyl reacts in both the oxygen (air) and oxygen-free mediums via both the direct and sensitized reactions. The photochemical mechanisms are hypothesized and argued for the oxidative and non-oxidative decompositions. The haloxyfop-ethoxyethyl (Zellek) residues lbrmed on foliage upon pesticide treatments of agricultural fields would essentially decompose under sunlight via a direct photoreaction in 4-6 weeks, but the propiconazole (Tilt) contaminants probably need more time.  相似文献   

14.
The main results of hydrocracking of goudron under reduced pressure in the presence of a suspended catalyst have beenanalyzed. It was investigate the influence of temperature to hydrocracking process of goudron. It was determined that with increasing of temperature from 400 ℃ to 440 ℃ (0.5 MPa pressure) the yield of light oil products increased from 31.39% to 61% mass.  相似文献   

15.
In this work study, we investigated possibility of modifying the new Michaelis Allen, Milobendzky-Shulgin, Michaelis-Becker, Raymond reactions with organic compounds of arsenic, antimony and bismuth is discovered. A new mechanism for possible reactions has been proposed.  相似文献   

16.
In this study, a comprehensive three-dimensional dynamic model was developed for simulating the flow behavior and catalytic coupling reactions for direct synthesis of dimethyl ether (DME) from syngas including CO2 in a fixed bed reactor at commercial scale under both adiabatic and isothermal conditions. For this purpose, a computational fluid dynamic (CFD) simulation was carried out through which the standard κ-ε model with 10% turbulence tolerations was implemented. At first, an adiabatic fixed bed reactor was simulated and the obtained results were compared with those of an equivalent commercial slurry reactor. Then the concentration and temperature profiles along the reactor were predicted. Consequently, the optimum temperature, pressure, hydrogen to carbon monoxide ratio in the feedstock and the reactor height under different operation conditions were determined. Finally, the results obtained from this three-dimensional dynamic model under appropriate industrial boundary conditions were compared with those of others available in literature to verify the model. Next, through changing the boundary conditions, the simulation was performed for an isothermal fixed bed reactor. Furthermore, it was revealed that, under isothermal conditions, the performed equilibrium simulations were done for a single phase system. Considering the simultaneous effects of temperature and pressure, the optimum operation conditions for the isothermal and adiabatic fixed bed reactors were investigated. The results of the H2+CO conversions indicated that, under isothermal condition, higher conversion could be achieved, in compared with that under adiabatic conditions. Then, the effects of various operating parameters, including the pressure and temperature, of the reactor on the DME production were examined. Ultimately, the CFD modeling results generated in the present work showed reasonable agreement with previously obtained data available in the literature.  相似文献   

17.
Naloxone is a well-known opioid antagonist indicated for the treatment of CNS (central nervous system) and respiratory depression induced by natural or synthetic opioid in adults and neonates whose mothers have received opioids. While it has been reported that an injection of 0.2 mg/mL of naloxone hydrochloride is physically and chemically stable, data on photostability on continuous i.v. infusion of 0.2 mg/mL of naloxone hydrochloride has not been reported. Therefore, a method was required for assessment of naloxone hydrochloride photostability. A high performance LC-MS (liquid chromatography/mass spectrometry) method was established to evaluate the photostability of naloxone hydrochloride. Injections of naloxone hydrochloride in 0.9% sodium chloride were exposed to artificial light and stored at room temperature (22 ~C) and 37 ~C. Naloxone losses up to 9.79% of its initial concentration when exposed to light at room temperature for 192 h, but the degradation increased up to 14.91% as the storage temperature increase. The disappearance of naloxone hydrochloride was correlated with the appearance of nor-oxymorphonedegradant. Naloxone hydrochloride is photosensitive and degradation increased at highly temperature and light intensity. Therefore, naloxone i.v. infusion solutions should either be protected from light and/or be frequently replaced when being administered to patients.  相似文献   

18.
It has been more than half a century since the release of the first Shimadzu UV-VIS (UV-visible) spectrophotometer QB-50 in 1952, and during this time more than 160,000 UV-VIS spectrometers have been produced and installed in a wide variety of different applications. A lot of technical innovations have been implemented to improve the performance and significantly reduce the stray light levels. The latest innovation during development of sophisticated spectrophotometers is based on a new holographic exposure method and optimized etching process which has made it possible to produce both high-efficient and exceptionally low stray light gratings. These LO-RAY-LIGH~ gratings have guaranteed values of stray light at the intermediate position between zero-order and first-order lights. The values are measured by Shimadzu's laser stray-light-measuring system. The latest development in the series of UV-VIS spectrophotometers is the UV-2700 which is a true double beam double monochromator system in a compact design for high-precision spectral analysis of a wide range of samples including organic and inorganic compounds, biological samples, optical materials and photovoltaics. The high performance optical system is designed with "LO-RAY-LIGH" diffraction gratings, featuring highest efficiency and exceptionally low stray light. The spectrophotometer operates in the wavelength range from 185 nm to 900 nm and allows highly sophisticated applications such as direct measurement of high density samples up to 8 absorbance units without dilution.  相似文献   

19.
《天然气勘探与开发》2014,(4):I0001-I0010
Recently, an exploration for the bioreef and shoal reservoirs in Changxing and Feixianguan formations, Jiulongshan-Jiange area, has gained a great breakthrough. And a study on the reservoirs continues to deepen. Moreover, along with these comes a great awareness of reservoir characteristics. For the Changxing Formation, the reservoir is dominated by crystalline and granule dolomites with developed pores (dissolution pore and karst cave) and fractures, which belongs to moderate- to high-porosity and moderate- to high-permeability fractured-porous reservoir. The Feixianguan Formation is mainly composed of granule limestones with developed intragranular and intergranular dissolution pores, which belongs to low-porosity and low-permeability reservoir. And its types include porous-fractured reservoir and fractured-porous reservoir. It is deemed after a comprehensive analysis that (1) favorable facies may affect reservoir development and distribu- tion and is an important factor to form Changxing and Feixianguan reservoirs in this area; (2) both dolomitization and dissolution can greatly improve the physical property, which are the key to de- velop high-quality reservoirs; and (3) structural rupture is conducive to reservoir development.  相似文献   

20.
MCC (micro crystalline cellulose) is a very important product in pharmaceuticals, foods, cosmetics and other industries. MCC can be made from any natural cellulose materials that have high content of cellulose ranging from pure cellulose, commercial grade cellulose to lignocellulosic materials. In this work, Beeswing (-20 L) and Chaff (5/8) which are the parts of corn cobs were used as raw materials to produce MCC via alkaline degradation, bleaching and hydrolysis. The optimum conditions of alkaline degradation, bleaching and hydrolysis were studied. MCC samples that prepared from -20 L and 5/8 were characterized through XRD (X-ray diffraction), SEM (scanning electron microscopy) and compared with the commercial MCC (Avicel PH 101). The results show that the degree of crystallinity of alkaline degradation, bleaching and hydrolysis obtained at 10% of NaOH 95 ~C for 2 h, NaCIO21.5 g 10% of acetic acid 0.5 mL 70 ~C for 2 h, 2 N of HC1, 105 ~C for 1 h showed maximum values which are 77.07%, 75.07% and 86.84%, respectively. The degree of crystallinity and the morphology of prepared MCC correspond to that of Avicel PH 101 industrial investment has been studied, the benefits of micro crystalline cellulose production (MCC) is 3,447 baht/kg. The investment of the plant is 7,263,514 baht and the breakeven point is around 6 years.  相似文献   

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