Linear correlation between pH value of stimulated beef and electrical current intensity

The aim of the present study was to determine mathematical relationships between pH changes in beef 24 h post-slaughter and changes in the intensity of electrical current flowing through bull and heifer carcasses during high-voltage electrical stimulation. The electrical stimulation was applied 40 min postmortem for 120 s. The pH values of m. longissimus thoracis et lumborum were analyzed in the function of electrical current intensity changes and its change during electrical stimulation. Mathematical linear correlations of the y = ax ± b type were demonstrated between pH values at 2, 6, and 24 h postmortem and the initial (I_i) and ultimate (I_u) electrical current intensity values, the difference between them and the initial pH values determined before electrical stimulation. High multiple correlation coefficients (R² = 0.416, α ≤ 0.001) between I_u and pH values 24 h post-slaughter enabled concluding that there is a possibility to predict a pH value of stimulated carcass with high accuracy, and thus also beef quality, based merely on the ultimate electrical current intensity values.     

一种家用手持式红外偏振光治疗仪的设计与实现

红外偏振光治疗仪是一种将红外技术与电子技术应用到医学领域的康复理疗设备,主要用于软组织损伤和慢性疼痛的康复治疗,已在医院得到了推广使用。然而,现有医院使用的台式治疗仪由于体积大、售价高等特点,不方便居家使用。为了开发体积小、售价低、家庭可用的红外偏振光治疗仪,满足家用市场的潜在需求,本文提出了一种新的便携手持式红外偏振光治疗仪,并开发了该智能控制系统。本文首先介绍了一种新的家用手持式治疗仪应具备的特点和关键技术指标,在此基础上设计了手持式治疗仪的硬件总体方案和软件架构,简要介绍了该治疗仪的一些关键技术,最终实现了治疗仪样机的研制。为了验证该样机的性能,本文通过大量的测试,结果表明,研制的手持式红外偏振光治疗仪在关键参数指标上达到了医院同类产品的水平,能够很好地满足家用的需求,具有良好的市场前景。     

Mineralization of Para-Chlorobenzoic Acid in Water by Cobalt-Incorporated MCM-41 Catalyzed Ozonation

Cobalt-incorporated MCM-41(Co-MCM-41) was used as a heterogeneous catalyst for the ozonation of para-chlorobenzoic acid (p-CBA) in aqueous solution. Cobalt oxide supported on MCM-41(Co/MCM-41) was synthesized for comparison. Their textural properties were elucidated by various characterization techniques to understand the relationship between surface texture and catalytic activity. TOC removal at 60 min reached 91% with Co-MCM-41, 83% with Co/MCM-41 and only 52% with ozone alone, respectively. Observations from diffuse reflection spectroscopy demonstrated that different metal phases were formed in these cobalt-modified molecular sieves samples. Radical scavenger experiments indicated the formation of hydroxyl radicals that were responsible for the effective degradation of p-CBA. An integrated approach to the catalytic mechanism was proposed by considering the variation of pH in the course of ozonation as well as its subsequent influence on the dissociation of targeted compounds and surface charge of the catalyst. In the reusability experiments, the reused Co-MCM-41 was able to regain the same catalytic capability as the fresh one within 5 cycles. X-ray photoelectron spectroscopy results indicated that a part of Co²⁺ was oxidized to Co³⁺ after oxidation reaction.     

Chitosan Microspheres as Carriers for pH‐Indicating Species in Corrosion Sensing

Chitosan microspheres containing bromocresol green, cresol red, and phenolphthalein for corrosion detection, through pH change, are synthesized in order to be used in protective coatings for aluminium alloys. Microspheres containing corrosion detection species are characterized morphologically (SEM) and physico‐chemically (FTIR, TGA). Release studies (UV–vis) are performed in corrosion‐promoting conditions (pH, NaCl), and detection studies by immersion in media associated with corrosion activity while microspheres' sensing activity is evaluated visually. Electrochemical characterization of AA2024 substrates in the presence of chitosan spheres is performed to understand material performance, and a color change is observed as a result of local pH increase in cathodic areas when corrosion takes place. These findings can be correlated with the results from release studies and seem a promising approach for corrosion sensing purposes, not only because pH increase is possible to detect due to corrosion, but also because chitosan is considered an environmentally friendly material.     

增效过磷酸钙的增效机制及其对玉米生长的影响

利用猪毛、风化煤和腐植酸钠的水解液为增效剂制备了一种增效过磷酸钙,探讨了增效过磷酸钙的增效机制及其对玉米生长的影响。结果表明,蒸馏水浸提条件下,增效过磷酸钙能减缓水溶磷的释放,具备较高的pH值缓冲性。与普通过磷酸钙相比,增效过磷酸钙处理的玉米生物量平均增加了41.9%,吸磷量和吸钙量分别增加了61.7%和27.8%,根系活力增加了24.3%。该研究结果对过磷酸钙生产的技术改进具有指导意义。     

丙烯酸/α-甲基丙烯酸/丙烯酰胺共聚物智能水凝胶的合成及评价

由丙烯酸（AA）、α-甲基丙烯酸（MAA）和丙烯酰胺（AM）合成了具有很好DH敏感性和一定温度敏感性的智能水凝胶，考察了合成温度、丙烯酰胺、交联剂和引发剂用量对制备的水凝胶溶胀性能的影响。结果表明，在60℃下，单体从和MAA用量分别为100mmol和75mmol时，单体AM、交联剂和引发剂用量分别为反应物总质量的32．8％、0．2％和0．4％时，制备的水凝胶溶胀性能最好。考察了介质的离子浓度、pH值和温度对水凝胶溶胀比的影响，结果表明，离子浓度越大，水凝胶的溶胀比越小；水凝胶具有一定的DH可逆性。     

铁路罐车密闭装车计量系统的运行分析

从中国石化股份公司济南分公司新上铁路罐车密闭装车计量系统的背景出发，阐述该系统的设计思想和组成；通过分析实际运行过程中仪表比对数据，讨论影响仪表贸易交接准确性的各种因素，提出相应的解决方法；最后通过铁路罐车密闭装车计量系统投用效果。证实该系统可产生明显的经济效益。     

聚乙烯辐照接枝体系中添加金属盐对接技率的影响

采用辐照接枝的方法，在高密度聚乙烯(HDPE)上接枝丙烯酸(AA)和对苯乙烯磺酸钠(SSS)，从而削备出了一种含羧酸基团和磺酸基团的阳离子交换膜。详细研究了接枝体系中引入添加剂醋酸钠或氯化钠对接枝率的变化规律．实验表明，在预辐照接枝和共辐照接枝中，当AA接技PE或AA与SSS共同接枝PE时，强碱弱酸盐醋酸钠通过pH效应同离子效应对接枝率呈现复杂的影响，而中性盐氯化钠经离子对效应显著提高接枝率。     

Novel application of radiotracer techniques for corrosion studies of zinc and aluminium in acidic medium

The adsorption of sulphate ions on Zn and Al was studied in 0.5 M NaClO₄ supporting electrolyte at various pH values in the range of pH=2-7 by radiotracer techniques. It was found in both cases that the adsorption of sulphate passes over maximum in the pH range studied.The phenomena observed are interpreted by the assumption that the main component of the overall process is anion adsorption on the protonated oxides/hydroxides formed as a result of corrosion. At low pH values the steady state coverage with respect to these products should be very low owing to their dissolution; consequently the extent of anion adsorption induced must also be very low. At higher pH values where no protonation occurs the adsorption of anions decreases significantly.