Coupled heat/mass-balance model for analyzing correlation between excess AlF_3 concentration and aluminum electrolyte temperature

The influence of aluminum electrolyte component on its temperature is an important issue within the field of aluminum reduction with pre-baked cells. The characteristic correlation between excess AlF3 concentration and aluminum electrolyte temperature was explored through the modeling of heat and mass transfer processes in industrial pre-baked aluminum reduction cells. A coupled heat/mass-balance model was derived theoretically from the mass and energy balance of an electrolysis cell, and then was simplified properly into a practical expression. The model demonstrates that if environmental temperature and Al2O3 concentration keep constant, the excess AlF3 concentration decreases with the aluminum electrolyte temperature linearly and its decrease rate is dependent on the heat transfer property of aluminum electrolyte, side wall and cell shell. Secondly, experiments were conducted on site with two industrial cells in an aluminum electrolysis plant. Excess AlF3 concentration and aluminum electrolyte temperature were obtained simultaneously together with other parameters such as Al2O3, CaF2, MgF2 and LiF concentrations. Results show that the maximum absolute error between the tested value and the calculated value of excess AlF3 concentration using the proposed model is less than 2%. This reveals that the coupled heat/mass-balance model can appropriately characterize the correlation between excess AlF3 concentration and aluminum electrolyte temperature with good accuracy and practicability.

Blood Chemistry, Acid-Base, Electrolyte, Blood Lactate Metabolism and Sleep at 3480 m in Mountain Marathon Runners

Altered blood chemistry, acid-base and electrolyte are suggested determinants of sleep disturbance, with frequent arousal at high altitude even in well and long-trained altitude marathon runners. In this sample of experienced altitude marathon runners with maximal aerobic power at sea level of 61.4 ± 2.7 ml/kg-1·min-1 we found that pO2 and percent of oxygen saturation (%SO2) were lower at2050 mand3480 mthan at sea level;pO2 was higher after 38 - 41 hours than after 30 - 31 hours of acclimatization at3480 m(P 2 decreased (P 2 and (P 2 at a sleeping altitude of3480 mwas lower (P Simple regression analysis disclosed a significant correlation between the changes in TST and the percent of REM sleep and the changes in %SpaO2 recorded during sleep (P 2 at higher altitude and the percent of W and of TST (P 2, tCO2 and [HCO3-] correlated negatively and significantly with the percent of REM sleep changes at high altitude (P 2 and pH and correlated negatively with the changes in %SO2, pCO2, tCO2, and [HCO3-] (P ++] and [BE] and negatively with the changes in buffered bases [BB] and [BEeffective] (P 2 and significantly and negatively with the changes in [K+] (P 2, tCO2, [HCO3-] and [K+]

Reducing Sharp Fluctuations in Body Temperature and Optimizing Production Index of Broilers Using Dietary Electrolytes

A degree centigrade fall or rise in body temperature of broiler chickens is sufficient to reduce performance, alter sound physiological state and divert nutritional metabolism in quest for ensuring thermal balance. Thermoregulatory mechanisms of newly hatched chicks are poorly developed, and fluctuations in brooding temperature coupled with severe environmental temperatures in the tropics could threaten the survivability, production and economic integrity of fast-growing strains of broilers. However, information on the effect of sharp fluctuations in body temperature on nutrient intake and European production index (EPI) of broilers fed dietary electrolytes is scanty and thus investigated. Using a total of 300, one-day-old unsexed broiler chicks (Arbor Acre) that were randomly allotted to six dietary treatments (T1-210, T2-240, T3270, T4-300, T5-330 and T6-360 mEq/kg electrolyte balance), data on performance characteristics and their correlations with body temperature and EPI at prestarter, starter and finisher phases were determined using standard procedures. Data were analysed using descriptive statistics and ANOVA at α = 0.05. At prestarter phase, feed intake (FI) had a strong and positive relationship with protein intake (r = 1.00;p < 0.01), EPI (r = 0.96;p < 0.01) and potassium (K) intake (r = 0.66;p < 0.01), but was negatively correlated with temperature change (r = ?0.39;p < 0.05). However, FI was not significantly correlated with body weight (BW), body weight gain (BWG), sodium (Na) and water intake. At starter phase, EPI was positively correlated to K intake (r = 0.38;p < 0.05), but not Na and chloride (Cl) intake. European production index of starter chicks could be enhanced by increasing the level of K intake through dietary supplementation up to 1.02%. Weight gain was adversely affected by sharp changes in temperature at finisher phase. Increase in water intake may not be a remedial tool in lowering sharp fluctuations in body temperature. However, sharp fluctuation in body temperature of broilers was reduced with DEB of 330, 270 and 240 mEq/kg at prestarter, starter and finisher phases, respectively.

Study on acid-base disorders in patients with adult respiratory distress syndrome

Arterial blood gases and electrolytes were determined in 159 cases of adult respirato-ry distress syndrome(ARDS).It was found that disordered acid-base balance was a commonfinding in various kinds of ARDS.In mild ARDS,respiratory alkalosis and the combination ofrespiratory alkalosis plus metabolic alkalosis or metabolic acidosis were usually encounted,whilein moderate and severe cases of ARDS,triple acid-base disorders,respiratory acidosis,and thecombination of respiratory acidosis plus metabolic acidosis were commonly seen.Severe alkalosiswas one of the factors to result in death.

Electrochemical behaviors of novel composite polymer electrolytes for lithium batteries

A novel composite polymer electrolyte was prepared by blending an appropriateamount of LiClO_4 and 10 percent (mass fraction) fumed SiO_2 with the block copolymer of poly(ethylene oxide) (PEO) synthesized by poly (ethylene glycol) (PEG) 400 and CH_2C1_2 The ionicconductivity, electrochemical stability, interfacial characteristic and thermal behavior of thecomposite polymer electrolyte were studied by the measurements of AC impedance spectroscopy, linearsweep voltammetry and differential scanning calorimetry (DSC), respectively. The glass transitiontemperature acts as a function of salt concentration, which increases with the LiClO_4 content.Lewis acid-base model interaction mechanism was introduced to interpret the interactive relationbetween the filled fumed SiO_2 and the lithium salt in the composite polymer electrolyte. Over thesalt concentration range and the measured temperature, the maximum ionic conductivity of thecomposite polymer electrolyte (10^(-4.41) S/cm) appeared at EO/Li=25 (mole ratio) and 30 deg C, andthe beginning oxidative degradation potential versus Li beyond 5 V.

Generalized Electron Balance for Dynamic Redox Systems in Mixed-Solvent Media

A complex example of electrolytic redox system involving 47 species, 3 electron-active elements and five (3 am-phiprotic + 2 aprotic) co-solvents, is presented. Mixed solvates of the species thus formed are admitted in the system considered. It is proved that the Generalized Electron Balance (GEB) in its simplest form obtained according to the Approach II to GEB is identical with the one obtained for aqueous media and binary-solvent system, and is equivalent to the Approach I to GEB.

Recent advances in selective C–C bond coupling for ethanol upgrading over balanced Lewis acid-base catalysts

Ethanol is a considerable platform molecule in biomass conversion,which could be acquired in quantity through acetone-butanol-ethanol(ABE)fermentation.People have been working on the upgrading of ethanol to value added chemicals for decades.In the meantime,1-butanol and a series of value added products have been selectively generated through C–C bond coupling.In this mini-review,we focus on the recent advances in selective C–C bond formation over balanced Lewis acid-base catalysts such as modified metal oxide,mixed metal oxide,hydroxyapatite and zeolite confined transition metal oxide catalysts.Among them,Pd-MgAlO_x and Sr-based hydroxyapatite exhibit>70%1-butanol selectivity,while Zn——xZr_yO_z and Ta-Si BEA zeolite achieve>80%of isobutene and butadiene selectivity respectively.The mechanism and reaction pathway of C–C bond formation in each reaction system are described in detail.The correlation between C–C bond coupling and the acidity/basicity of the Lewis acid-base pairs from the surface of the catalysts are also discussed.

General Relation Valid for Electrolytic Systems

A simple general relation P = Q + R + 1 between the number P of kinds of species, the number Q of charge and elemental/core balances and the number R of independent equilibrium constants is deduced, and its validity is confirmed for non-redox and redox electrolytic systems, of different degree of complexity.

无机化学中“酸碱解离”教学内容的重构探讨

依据素质教育中知识-能力-素质有机融合的思想指导,对《无机化学》酸碱解离内容进行重组,构建新的课程设计模块。内容重组扩充为5个模块,包括电解质溶液基础、酸碱理论概述、酸碱强度、弱酸弱碱解离平衡和酸碱滴定与误差基本概念。教学内容的重构在保证基本面知识结构完整的前提下与时俱进,从专业能力方面促进学生发展。

饲粮电解质平衡的生物学作用及其在畜禽生产中的应用研究进展

电解质是指在水溶液中能够解离成带电离子的化合物,其主要组成元素包括钠(Na^(+))、钾(K^(+))、氯(Cl^(-))、钙(Ca^(2+))、镁(Mg^(2+))等离子。饲粮电解质平衡(dEB)是指在畜禽饲粮中,不同电解质或正、负离子的含量和比例均达到适宜范围,以满足动物的生理需求并维持其正常生理功能。作为饲粮配方设计的关键要素之一,适当的dEB值可以有效提高饲粮营养物质利用率,改善动物健康状况,促进生长发育,对提高养殖业的经济和社会效益具有重要意义。因此,本文旨在对dEB的生物学作用及其在畜禽生产中的应用研究进展进行综述,以期为养殖业的可持续发展提供参考。

钢棒保温改善石墨化阴极电解槽能量平衡的实践

近年来石墨化阴极炭块凭借其优异的性能被电解铝行业所青睐。但部分企业只将阴极及其他部分内衬材质做了改变,磁场及母线配置并未调整,导致电解槽能量平衡不匹配,出现电解槽偏冷、伸腿肥大等现象,影响电解槽的正常生产。本文采取对全石墨阴极电解槽进行钢棒保温这一措施,有效减少电解槽散热,通过对钢棒保温前后的温度、效应系数、以及电压差值进行对比分析,有效证明该措施有效,最终达到引导电解槽能量趋于平衡的目的。

胸部开放伤后海水浸泡对实验犬血浆渗透压及电解质平衡的影响

目的 :探讨胸部开放伤后海水浸泡对实验犬血浆渗透压和电解质平衡的影响。方法 :实验动物致伤后随机分为对照组 (n=10 )、海水浸泡组 (n=10 )和生理盐水浸泡组 (n=5 )。对照组为单纯胸外伤。海水浸泡组和生理盐水浸泡组动物于致伤后分别置入人工配制的海水或生理盐水中 ,于致伤前及入水 15、30、45分钟及 1、2、3和 4小时取血测定血浆渗透压、血钠、血钾、血氯 ,同时监测血流动力学变化。结果 :海水浸泡组动物有严重的电解质紊乱和血液高渗状态 ,表现为高渗综合征、高钠血症和高氯血症 ,而对照组和生理盐水浸泡组致伤前后无明显变化。结论 :海水浸泡对机体血浆渗透压和电解质平衡有严重影响 ,是实验犬致死的重要原因之一。

复方果糖电解质注射液在肾移植后多尿期补液中的临床应用研究

目的 观察复方果糖电解质注射液在肾移植术后多尿期的补液效果。方法 回顾性分析2004年1月－2013年12月上海长征医院1279例肾移植后多尿期的补液治疗方案，均采用复方果糖电解质注射液补液，监测患者的血电解质、血糖、尿糖、二氧化碳结合力（CO2CP）及肾功能变化情况。结果 肾移植后多尿期尿量峰值出现在术后3～9h，其中最高尿量达到2500ml/h。血钠、钾、氯均在正常范围，血钙处于正常范围的下限，CO2CP在正常范围，血肌酐浓度随时间推移而明显下降。术前患者血糖均控制在正常范围内，术后血糖水平略有上升，但多处于正常范围上限或者稍高于正常值，且术后1周内未出现血糖的剧烈波动。尿糖受手术的影响更小，术后无升高趋势。结论 复方果糖电解质注射液可较好地维持肾移植后多尿期的水、电解质和酸碱平衡，并能有效解决传统循环补液治疗存在的液体种类多、操作繁琐和高血糖等问题。

原位肝移植围术期血液酸碱和电解质变化

目的探讨原位肝移植围术期血液酸碱、电解质变化及麻醉处理。方法18例终末期肝病行原位肝移植术患者,分别于无肝前期、无肝期10、20、30min、新肝期10、20、30min测定动脉血pH、PaO2、PaCO2和肺动脉混合静脉血HCO3-、SvO2、K+、Ca2+、Na+和Hct。结果与无肝前期时相比,无肝期20min时pH值明显升高(P<0.05),随后在新肝期10、20min时逐渐下降;而PaCO2和HCO3-自无肝期20min以后都保持不同程度的升高(P<0.05或P<0.01)。新肝期10、20、30min时Hct和PaO2均明显升高(P<0.05或P<0.01),血Na+浓度均明显降低(P<0.05),血K+浓度在无肝期10min时升高(P<0.05),而新肝期10min时又明显降低(P<0.05);血Ca2+浓度基本保持稳定,只是在无肝期30min时比无肝前期时略有升高(P<0.05)。SVO2在无肝前期时较高,但在无肝期30min时较无肝前期时显著降低(P<0.05),在新肝期又回升至无肝前期时水平。结论原位肝移植术中酸碱和电解质变化较大,围术期适时监测血酸碱、电解质变化有助于维持血流动力学的稳定和预防再灌注综合征的发生。

补肾活血方治疗骨质疏松症机制研究及探讨

目的研究补肾活血方(熟地、杜仲、制附子、枸杞、肉桂、山茱萸、桃仁、红花、山药、甘草)对微循环障碍小鼠的活血作用及对正常小鼠动脉血电解质、血氧量、酸碱平衡等指标的影响。方法①采用注射垂体后叶素造成尾部微循环障碍小鼠模型。各组小鼠连续给药10 d,末次给药1 h后,检测小鼠尾部微循环血流值相对比值,尾静脉注射垂体后叶素0.02 u,2 min后再次检测,计算注射前后两者之差;②采用戊巴比妥钠麻醉后测定动脉血中电解质、酸碱平衡及血氧量。各组小鼠连续给药10 d,末次给药1 h后,腹腔注射戊巴比妥钠麻醉,腹主动脉取血0.6 mL,NOVA血气-电解质分析仪测定动脉血中电解质、酸碱平衡及血氧量指标。结果与正常对照组比较,补肾活血方(20 g/kg)能增加由注射垂体后叶素所致的小鼠尾部微循环血流比值;与正常对照组比较,补肾活血方(40 g/kg)能显著性减少小鼠腹腔动脉血中的Na+、Ca2+浓度;显著性降低小鼠腹腔动脉血酸碱平衡中的BE-ECF、SBC;显著性增加小鼠腹腔动脉血中的PO2、a/A、PO2/FI值(P<0.05～0.01)。结论补肾活血方通过协调钙离子吸收、提高血液载氧量、改善血液微循环以及调整酸性体质等多方面因素,发挥预防和治疗骨质疏松作用。

快速输注低张液体在治疗胸外伤后海水浸泡致高渗血症中的作用

目的 :探讨快速输液在海水浸泡性胸外伤致高渗血症治疗中的作用。方法 :实验犬致伤后随机分为对照组 (10只 )和治疗组 (10只 )。对照组于胸外伤后置入人工配制的海水中 ,观察期间不予任何治疗 ;治疗组于浸入海水 2 5分钟后捞出进行紧急救治 (包括关闭伤口、胸腔闭式引流以及于 4小时内快速输入低张液体 ,输液量为总补液量的 1/ 2 )。于不同时间点取血测定血浆渗透压、血钠、血钾、血氯和动脉血气。结果 :对照组和治疗组均于浸泡海水后出现严重高渗血症、高钠血症和高氯血症。对照组在实验期间的死亡率为 90 % ,平均生存时间为 45分钟。而治疗组经胸腔闭式引流和快速输入低张液体后 ,平均血浆渗透压于 2 4小时回落到伤前基础水平 ,全组平均存活时间为 40 .9小时 (治疗组中 5只犬存活时间 <2 4小时 ,死亡前平均血浆渗透压为377mm ol/ L,平均存活时间为 14.7小时 ;而存活时间超过 2 4小时的 5只犬平均血浆渗透压为 30 9mm ol/ L,平均存活时间为 6 7.2小时 )。结论 :胸外伤后海水浸泡对机体的血浆渗透压和电解质平衡有严重影响 ,是实验犬致死的重要原因之一。早期快速输入低张液体对降低血浆渗透压。

散打、跆拳道运动员赛前体重控制的实验研究

对上海体育学院重竞技训练中心散打、跆拳道运动员在赛前慢性控制体重基础上进行亚急性控重。结果:运动员的体重下降,体脂百分比下降,瘦体重变化不大,运动员的体内离子保持平衡,机能状态和运动能力并没有受到明显影响。

钠钾镁钙葡萄糖注射液扩容对术中血糖、电解质和酸碱平衡的影响

目的比较钠钾镁钙葡萄糖注射液和复方乳酸钠注射液扩容对术中血糖、电解质及酸碱平衡的影响。方法择期行胃肠道手术患者30例,采用随机数字法分为研究组(n=16)和对照组(n=14),研究组使用钠钾镁钙葡萄糖注射液扩容,对照组使用复方乳酸钠注射液扩容,分别在入室后以15ml·kg-1·h-1的速度输注相应液体。分别于输液前(T0)、输液量为10ml/kg(T1)、20ml/kg(T2)和30ml/kg(T3)时检测患者血糖、血乳酸、电解质及pH值等。结果输液后研究组血糖明显升高(P<0.05),血乳酸无明显变化,血pH明显降低(P<0.05);对照组血乳酸明显升高(P<0.05);两组电解质水平均无明显变化。结论钠钾镁钙葡萄糖注射液在扩容、维持电解质及酸碱平衡方面与复方乳酸钠注射液效果相当,可避免大量输入复方乳酸钠注射液所致的乳酸升高,但当大量输注钠钾镁钙葡萄糖注射液时可导致一定程度的血糖升高。

多氯联苯对鲫鱼血液电解质的影响

研究了水中多氯联苯（ＰＣＢｓ）对鲫鱼血液电解质平衡的影响。结果显示鲫鱼在受到ＰＣＢｓ污染后，血清中电解质的平衡会受到影响．在本实验范围内Ｎａ＋的含量明显高于正常水平，并随试验浓度的增加而逐步升高同时随暴露时间的增长而升高；Ｋ＋含量低于正常值，并随试验浓度的增加而降低，同时随暴露时间的增长而降低；而对于Ｃａ２＋、Ｍｇ２＋的影响无显著变化规律．

肝移植患者术中酸碱和电解质的变化与ASA分级关系及麻醉处理

目的观察肝移植患者术中酸碱平衡和电解质的变化与ASA分级的关系,并探讨其处理方法。方法选择89例行原位肝移植(OLT)的患者,其中ASA分级Ⅲ级27例、Ⅳ级46例、Ⅴ级16例,分别于麻醉前(T0)、切皮后(T1)、复灌前10min(T2)、复灌后10min(T3)监测动脉血中pH、PaO2、PaCO2、HCO3-、BE、K+、Ca2+、Na+和血糖的变化,并对不同ASA分级患者的监测结果进行比较。结果在T0、T1、T2、T3时段ASAⅤ级患者的pH和BE值明显低于其他患者;在T3时段ASAⅤ级患者的HCO3-低于其他患者;在T0、T1、T2时段ASAⅤ级患者的PCO2明显高于其他患者;在T2、T3时段ASAⅤ级患者的Na+明显高于其他患者;在T0、T1时段,ASAⅣ和Ⅴ级患者的血糖值高于ASAⅢ级患者。pH、PaO2、PaCO2、HCO3-、BE和血糖水平在手术的不同时段差异明显。pH、BE和HCO3-在T2和T3明显下降,血糖的水平从T1到T3逐渐升高。结论ASA高分级的患者在复灌时更容易出现酸碱和电解质紊乱,发生心血管虚脱的风险明显增高。