低弹性吸震发泡材料硫化特性的研究

研究开发了低弹性吸震闭孔式发泡材料,其力学性能符合adidas运动鞋材的标准.利用硫变仪研究了硫化条件和硫化特性,得出硫化交联反应速率常数k,表观活化能E,频率因子A以及硫化指数CCRI分别为9.96×10-3S-1,77.3kJ/mol,3.0×105和0.28S-1.确定了较适宜的硫化温度区间为(433～443K),最佳的硫化温度为438K.提出CCRI可作为确定正确的硫化交联反应温度的技术方法手段.

氢氧化钠溶液的微型电解池

一、微型实验电解装置取一多用滴管、在其圆筒吸泡和管径连接处相对打两个小孔。再取两段铁丝(用作电极,L=50mm,Φ=1mm),均用空的漆包线外套紧密地套住,两端露出15mm;外套和铁丝间的缝隙用粘胶剂(如509胶)密封,然后分别插入小孔至吸泡底部,用粘胶剂密封插孔,并使铁丝固定而不易松动。外露铁线端连接导线及一小电池(如9伏高能电池),即制得电解氢氧化钠溶液的微型装置。见下图。

微型化学实验在我校化学教学中的应用

微型化学实验在我校化学教学中的应用郑州铁路职工子弟第六中学（４５００５２）李秀云我校从１９９２年３月开始，在初、高中化学教学中采用微型实验，取得了良好的效果。现将做法和体会介绍如下：一、采用的微型实验仪器及其配套方法（１）主要仪器多用滴管，由聚乙烯等...

微型化学实验介绍

80年代化学实验教学改革的一个重大方面是采用微型化学实验。为了减少有机化学实验中,有机溶剂挥发对大气的污染和增加实验的安全性,在80年代初美国Dana W.Mayo博士等首先在有机合成实验中,减少有机溶剂的用量。于是所用的有机溶剂一般为几毫升,固体原料为几百毫克(约为常规实验的十分之一到数百分之一)。这样,就要在重新设计的微型化的仪器中进行实验。

Indentation of sandwich beams with metal foam core

The quasi-static indentation behavior of sandwich beams with a metal foam core was investigated. An analytical model was developed to predict the large deflections of indention of the sandwich beams with a metal foam core subjected to a concentrated loading. The interaction of plastic bending and stretching in the local deformation regions of the face sheet was considered in the analytical model. Moreover, the effects of the shear strength of the foam core on the indentation behavior were discussed in detail. The finite element simulations were preformed to validate the theoretical model. Comparisons between the analytical predictions and finite element results were conducted and good agreement was achieved. The results show that the membrane force dominates indentation behavior of the sandwich beams when the maximum deflection exceeds the thickness of the face sheet.

基于网络控制的门胆四工位真空成型机

研发了一种集网络控制、气压比例吸泡及脱模控制、液压比例控制、伺服控制等先进技术于一体的新型门胆四工位真空成型机,可广泛用于冰箱门胆的批量生产。

Relationship Between Tonoplast H^+-ATPase Activity, Ion Uptake and Calcium in Barley Roots Under NaCl Stress

Under NaCl stress for 2 d, H+-ATPase activity increased, and H+-PPase activity decreased in the tonoplast of salt-tolerant barley ( Hordeum vulgare L. cv. 'Tanyin 2') roots. La3+ (1 mmol/L), an inhibitor of Ca2+ channel in plasma membrane, and EGTA (5 mmol/L), a Ca2+ chelator, inhibited this NaCl-induced increase in H+-ATPase activity but stimulated the H+-PPase activity. Treatment of barley roots with CaM antagonist (trifluoperazine, TFP, 20 mumol/L) also diminished the increase of H+-ATPase activity induced by NaCl. La3+, TFP or La3+ + TFP increased Na+ uptake and decreased K+ and Ca2+ uptake in barley roots under NaCl stress. These results suggested that the activation of tonoplast H+-ATPase and the regulation of Na+ and K+ uptake under NaCl stress may be related to Ca2+-CaM system.

基于网络控制的多工位真空成型机的研究与开发

研究并开发了一种集网络控制、气压比例吸泡及脱模控制、液压比例控制、伺服控制等先进技术于一体的现代化集成制造系统——多工位真空成型机,可广泛用于火车内饰件、汽车内饰件和冰箱(柜)内胆的批量生产。

氨气的喷泉实验

教材中的喷泉实验主要分为两部分：首先,加热氯化铵和氢氧化钙制取氨气并把氨气收集在圆底烧瓶中;然后,在圆底烧瓶瓶口塞紧带有导管和胶头滴管的橡胶塞,把导管下端插入水中;最后,把胶头滴管中的水挤入烧瓶中,引发喷泉。上述方法操作烦琐,一不小心就会失败,再次进行实验就比较困难。

基于网络控制的门胆四工位真空成型机

本设备是一种集网络控制、气压比例吸泡及脱模控制、液压比例控制、伺服控制等先进技术于一体的新型门胆四工位真空成型机,可广泛用于冰箱门胆的批量生产。

电解水的微型实验

原理：给水通直流电电解,水分解,正极产生氧气,负极产生氢气,两者的体积之比为1：2。实验用品：多用滴管3支,珠针2枚,导线2根（带鳄鱼夹）,电池（9 V）,灯泡（带灯座）,烧杯,剪刀,微型酒精灯,火柴,细香,直尺,吹泡液;氢氧化钠溶液（5%）,稀盐酸。实验装置图：如图1所示。

Towards the Mechanism of Mass Transfer of a Single Bubble

This paper focuses on the mechanism of interfacial mass transfer of a single bubble, based on the chemical potential driving force, an approach for calculating interfacial concentration in practical process is proposed. The absorption processes of bubble under both quiescent and mobile conditions are analyzed and discussed respectively. For a stationary absorption, only in the case of liquid bulk concentration near saturated value, the interfacial concentration could close to the equilibrium value ; For a moving bubble, under ordinary operating condition （Yo〉l）, the interfacial concentration is far from its equilibrium. Only under bulk concentration near saturated value or a smaller Yo（Yo〈0.1） which may involve the complication of additional resistance at interface induced by surface contamination or surfactant added, the interfacial concentration could be approximate to equilibrium value. The interfacial concentration close to the interface on liquid side for a single CO2 bubble absorbed by methanol is measured using a modern optical instrumentation in which the laser holographic interference method is adopted with a real-time and amplification technique. Experimental results show that the interfacial concentration decreases significantly with increasing Re and is far from the equilibrium one in a larger Re range. Experiments validate the proposed model.

Application of modified sepiolite as reusable adsorbent for Pd(Ⅱ) sorption from acidic solutions

The adsorption characteristics and mechanisms of modified sepiolite as an adsorbent to recover Pd(Ⅱ) from acidic solutions were studied. The Pd(Ⅱ) adsorption properties were analyzed through isotherm, kinetic and thermodynamic models. In addition, SEM-EDS, TEM and XPS were applied to investigating the Pd(Ⅱ) adsorption mechanisms onto modified sepiolite. The equilibrium data were well fitted to Langmuir isotherm model with maximum Pd(Ⅱ) adsorption capacity of 322.58 mg/g at 30 ℃. The kinetic data could be satisfactorily simulated by the pseudosecond order model, indicating that the rate-controlling step was chemical adsorption. 99% of Pd(Ⅱ) could be recovered using 1 g/L modified sepiolite when initial concentration of Pd(Ⅱ) was 100 mg/L. The results of reusability studies indicated the modified sepiolite had an acceptable stability and reusability. This study indicated that the modified sepiolite might be an efficient and cost-effective material for Pd(Ⅱ) recovery.

Numerical simulation of a self-absorbing microbubble generator for a cyclonic-static microbubble flotation column

The Cyclonic-Static Microbubble Flotation Column (FCSMC) is currently a widely used, novel type of flotation device. The self-absorbing microbubble generator is the core component of this device. The structure of the microbubble generator directly influences flotation column performance by affecting bubble size and distribution as well as gas holdup in the column. However, the complicated flow inside the generator results in high R&D costs and difficulty in testing. Thus, the CFD software, FLUENT, was used to simulate the gas-liquid two-phase flow inside a self-absorbing microbubble generator. The effect of area ratio, a key structural parameter, was studied in detail. Critical flow-field parameters including velocity, turbulent kinetic energy, minimum static pressure and gas holdup were obtained. The simulation results demonstrate that the optimum area ratio is 3.

Mechanical properties and energy absorption properties of aluminum foam-filled square tubes

Longitudinal and transverse mechanical properties and energy absorption properties of foam-filled square tubes under quasi-static loading conditions were studied.The foam-filled thin-walled square tube was fabricated with aluminum tube as its shell and closed-cell Al-Mg alloy foam as its core.The results indicated that the plateau region of the load-displacement curve exhibited a marked fluctuant serration which was clearly related to the formation of folds.The longitudinal deforming mode of foam-filled square tube was the same as that of the empty tube,but the fold number of foam-filled square tube was more than that of the empty tube.The longitudinal compression load and energy absorption value of foam-filled square tube were higher than the sum of that of aluminum foam (alone) and empty tube (alone) due to the interaction between tube and filler.In transverse direction,the compression load and energy absorption ability of foam-filled square tubes were significantly lower than those in longitudinal direction.

Sound absorption performance of various nickel foam-base multi-layer structures in range of low frequency

Commercial3D reticular nickel foam and its composite structure were investigated on the sound absorption at200-2000Hz.The absorption performance of foam plates1?5layers(1-layer thickness:2.3mm;porosity:89%;average pore-diameter:0.57mm)was found to be poor,and could be improved by adding backed cavum or front perforated thin sheet.The absorption coefficient could reach about0.4at1000-1600Hz for the composite structure of5-layer foam with a backed5mm-thick cavum,and even0.68at about1000Hz for that of2-layer foam with the same cavum and a perforated plate closely in front of the foam.

Effect of Phenylephrine on Alveolar Fluid Clearance in Ventilator-induced Lung Injury

Objective To investigate the effect of phenylephrine （an α-adrenergic agonist） on alveolar fluid clearance （AFC） in ventilator-induced lung injury and the possible mechanism involved. Methods A total of 170 male Wistar rats were randomly allocated into 17 groups （n= 10） using ran- dom number tables. Short-term （40 minutes） mechanical ventilation with high tidal volume （HVT） was per- formed to induce lung injury, impair active Na＋ transport and lung liquid clearance in the rats. Unventilated rats served as controls. To demonstrate the effect of phenylephrine on AFC, phenylephrine at different con- centrations （1×10^-5, 1 ×10^-6, 1×10^-7, 1×10^-8, and 1×10^-9 mol/L） was injected into the alveolar space of the HVT ventilated rats. To identify the influence of adrenergic antagonists, Na＋ channel, and microtubular sys- tem on the effect of phenylephrine, phenylephrine at 1×10^-5mol/L combined with prazosin （an α1-adrener- gic antagonist, 1×10^-4 mol/L）, yohimbine （an α2-adrenergic antagonist, 1×10^-4 mol/L）, atenolol （a β1- adrenergic antagonist, 1×10^-5 mol/L）, ICI- 118551 （an β2-adrenergic antagonist, 1×10^-5 mol/L）, amiloride （a Na＋ channel blocker, 51×10^-4mol/L）, ouabain （a Na＋/K＋-ATPase blocker, 5~×10^-4mol/L）, colchicine （a mi- crotubular disrupting agent, 0.25 mg/100 g body weight）, or β-lumicolchicine （an isomer of colchicine, 0.25 mg/100 g body weight） were perfused into the alveolar space of the rats ventilated with HVT for 40 minutes. AFC and total lung water content were measured. Results Basal AFC in control rats was （17.47±2.56）%/hour, which decreased to （9.64± 1.32）%/hour in HVT ventilated rats （P=0.003）. The perfusion of phenylephrine at 1 ×10^-8, 1×10^-7, 1×10^-6, and 1×10^-5 mol/L significantly increased the AFC in HVT ventilated rats （all P〈0.05）. This effect of phenylephrine on AFC was suppressed by prazosin, atenolol, and ICI-118551 in HVT ventilated rats by 53%, 31%, and 37%, respectively （all P〈0.05）. The AFC-stimulating effect of phenylephrine was lowered by 33% and 42% with amiloride and ouabain, respectively （both P〈0.05）. Colchicine significantly inhibited the effect of phenylephrine （P=0.031）. Conclusion Phenylephrine could increase the AFC in HVT-ventilated rats and accelerate the ab- sorption of pulmonary edema.

Sound absorption of several various nickel foam multilayer structures at aural frequencies sensitive for human ears

Using the three-dimensional reticular nickel foam as experimental material, the sound absorption performance was investigated for several various multilayer structures in the frequency range of 2000-4000 Hz, which is aurally sensitive for human ears. The results showed that the 7.5 mm-thick foam sample, which was formed by piling of 5-layer foam plate（thickness： 1.5 mm; porosity： 96%; average pore-diameter： 0.65 mm） could exhibit an excellent sound absorption effect at 4000 Hz, with the absorption coefficient about 0.8. Constituting alternate air gap with the total thickness of about 18.5 mm can greatly improve the absorption performance at relatively low frequencies of 2000-3150 Hz, with the absorption coefficient up to about 0.5 or more. In addition, the research showed that alternate piling up the perforated plate inside the foam plates can also achieve a quite good effect of sound absorption at relatively low frequencies.

Cadmium sorption from aqueous solutions onto Iranian sepiolite:Kinetics and isotherms

This work aims to investigate the efficiency of Fariman sepiolite from Iran as an adsorbent to remove Cd from aqueous solutions. The effects of different experimental factors such as the initial Cd concentration, contact time and the sorbent dose were investigated through a series of batch adsorption experiments. The results show that the adsorption capacity of sepiolite for Cd increases with the contact time, the initial concentration of Cd solutions and the sorbent dose. Sorption of Cd by Fariman sepiolite is rapid within the first hour of the experiment and then slowly increases until a pseudo equilibrium is approached at 8 h. The results also show that the time-dependent Cd sorption data are better described with pseudo second-order （7〉0.999） than that of pseudo first-order （r2〉0.971） kinetic model. Equilibrium isotherm studies show that the experimental data are better correlated by the Freundlich adsorption isotherm （7〉0.995） than the Langmuir （P〉0.825）. It is suggested that both adsorption and cation exchange reactions are responsible for the sorption of Cd by the sepiolite, and the mineral has a very good potential to remove Cd from aqueous solutions.