大豆中硼形态研究及豆制品中硼形态调查

文章以大豆为研究对象,建立微波辅助分步连续提取方法并应用于大豆及大豆制品中硼形态及分布的分析研究。按照该方法可将大豆中硼大致分为有机态硼和无机态硼,而无机态硼又可分为水溶性硼、络合态硼、沉淀态硼。其含量分布为:大豆总硼含量为36.15 mg/kg,无机态硼含量为30.66 mg/kg,占总硼含量的84.8%,有机态硼含量为5.49 mg/kg,占总硼含量的15.2%;无机态硼中水溶性硼占57.7%,络合态硼占29.4%,沉淀态无机硼占12.8%。对10种常见大豆制品中硼形态研究发现:豆豉的有机态硼含量高达82.7%,而其他非发酵性豆制品中无机态硼为主要的硼形态,占总硼比例的64.2%~98.6%,表明豆制品中硼形态与加工工艺有关。本研究可以为内源性硼及外源性硼鉴别提供一定的借鉴。     

盐助自蔓延法制备无定型硼粉中硼含量的测定

采用多元醇强化硼酸法,以甘露醇为强化剂,酚酞为指示剂测定出盐助自蔓延法制备的无定型硼粉中三氧化二硼的含量,同时用原子吸收分光光度法测定出Mg含量,利用差减法最终得到了盐助自蔓延法制备出的无定型硼粉中的硼含量,硼含量为92.800%。这种测定硼含量的方法可以非常简单、便捷的测定出样品中硼的含量,并且此方法适宜于主量元素硼的测定。     

橡胶粘合增进剂硼酰化钴硼含量的测定及其对胶料性能的影响

采用电感耦合等离子体发射光谱（ICP-OES）法测定橡胶粘合增进剂硼酰化钴的硼含量,并研究硼酰化钴的硼含量对胶料性能的影响。结果表明：采用ICP-OES法能快速、准确地测定硼酰化钴的硼含量;硼酰化钴的硼含量与胶料性能具有较强相关性,硼酰化钴的硼质量分数为0.011-0.012时,胶料与钢丝帘线的粘合性能以及综合物理性能较好。     

硼原料对棕色硼硅酸盐玻璃性能的影响

研究了不同硼引入原料对棕色硼硅酸盐玻璃性能的影响,得出引入不同硼原料的玻璃,硼挥发量的实际排序;基于玻璃实际硼含量的差异,找出了氧化硼含量变化对玻璃光学透过率、玻璃高温黏度、玻璃膨胀系数性能指标影响的变化规律。     

复混肥中硼含量的测定方法

概述复混肥中硼含量现有的测定方法(比色法、酸碱滴定法、液相色谱法),比较它们的优缺点,针对不同复混肥特性及硼含量,探讨快速简便测定复混肥中硼含量的方法。     

深圳市食品中硼本底含量的调查研究

目的:了解深圳市部分食品中硼的本底含量,为科学监管提供依据。方法:在深圳市各超市、集贸市场及个体经营商店采集了产自全国各地的样品共计325份,用电感耦合等离子体发射光谱法检测样品中硼含量。结论:豆类和坚果类中的硼含量远高于其他食品原料,其次是蔬菜和水果,干制菌类折算为以鲜重计,则接近蔬菜的硼含量水平,大米和小麦粉中硼含量很低,肉类则大部分未检出。     

广东地区豆类天然硼砂含量的分析

文章对广东地区的豆类中硼砂本底进行了调查,结果表明:豆类均含有一定量的硼砂,不同产地的黄豆其硼含量存在差异,黄豆的硼含量范围在110.5~205.5 mg/kg之间,其中广州和河源地区黄豆中的硼含量低于韶关地区。其他种类的样品中,黑豆的硼含量较高达到219.0mg/kg。     

硼粉含量对Mg/PTFE富燃料推进剂性能的影响

为研究硼粉含量对镁/聚四氟乙烯(Mg/PTFE)富燃料推进剂性能的影响,采用混合模压成型工艺制备了7种不同硼粉含量的Mg/PTFE推进剂药柱。用红外测温仪、TG-DTA、量热仪分别测试其燃烧性能、热分解性能和爆热,并测试了其机械感度。结果表明,加入硼粉后,推进剂的燃烧性能明显改善,硼粉质量分数为15%时,线性燃速和质量燃速达到最高;当硼粉质量分数为20%时,燃烧温度达到最高;随着硼粉含量的增加,爆热稍微降低,完全燃烧热随着硼粉含量的增加而增大;当硼粉质量分数为10%时,高温放热峰温度降低128℃,撞击感度和摩擦感度达到最高值。     

钠硼硅玻璃分相的研究

应用扫描电镜、红外光谱等方法研究了钠硼硅玻璃分相过程中玻璃结构的变化.结果表明分相过程中,非桥氧含量增加,同时四配位硼含量降低.由于硅一般以四配位存在,所以当四配位硼含量降低时,硅氧网络和硼氧网络结构差异越来越大,最终导致分相.     

海水淡化后硼的脱除

西沙永兴岛电渗析淡化海水脱硼装置于1984年12月在永兴岛通过技术鉴定。该装置采用固定床离子交换工艺,填装564型硼特效树脂600升,可将电渗析淡化水中4.7毫克/升硼含量降到0.5毫克/升以下,每小时产水8立方米以上。硼在天然水中含量都比较低,大洋水中硼平均含量为4.6毫克/升。虽然微量硼对植物是营养元素。但过量的硼对植物、动物以及人体都是有害的。一九八一年在永兴岛建成我国第一座日产200吨淡水的电渗析海水淡化站,但淡化水中含硼4.7毫克/升。为保     

Vibrational Spectra of Vitreous B2O3.xH2O

The infrared absorption spectra of boron oxide glasses of low and high water content have been obtained in the 400- to 4000-cm.⁻¹ region using thin films or fine powders dispersed in a liquid. A structural interpretation of the glass spectra has been made with the aid of the spectra of the closely related materials boric acid, orthorhombic metaboric acid, and partly deuterated boron oxide glass of high water content. It has been shown that the glass spectra are consistent with a random-network structure in which each boron is triangularly coordinated by three oxygens and that the presence of water leads to weak hydrogen bonding between oxygen atoms. No evidence for a substantial amount of tetrahedral coordination of boron by oxygen has been found in glasses of either low or high water content.     

水中硼元素3种检测方法的比较

对水中硼的3种检测方法进行比较分析。甲亚胺-H分光光度法具有较高的精密度和准确度,可作为检测水中硼含量的仲裁方法;姜黄素分光光度法是测定水中硼含量的经典方法,但操作繁琐,稳定性不高;电感耦合等离子体质谱法(ICP-MS)简单易行、测定范围广,但设备昂贵,较难普及,可作为快速测定方法。     

Boron removal from saline water: A comprehensive review

Boron is an essential micronutrient for plants and animals as well as a useful component for numerous industries. It is necessary to produce low boron containing water from RO desalination plants for both human consumption and for agriculture. For plants, a small amount of boron is necessary for their growth and development, but boron becomes toxic if the amount is slightly greater than required. Desalinated seawater from RO plants often contains high boron content and, when used for irrigation, has been proven to be damaging to crops including blackberry, lemon, and grapefruit. Apart from the toxic effects of boron on plants, boron should be removed from RO desalination plants to comply with the current guideline value, 0.5 mg/L, for potable water issued by the World Health Organisation (WHO). Currently there is no simple method to remove boron from saline water. The use of multi-pass reverse osmosis membrane (RO) with pH modification and the use of ion exchange using boron selective resins (BSRs) have both been considered as effective methods for the removal of boron. A hybrid process, Adsorption Membrane Filtration (AMF), has received attention as an emerging technology for boron removal with a high efficiency and low operating costs. The purpose of this review is to give an overview on boron in general and to discuss its toxicity. The problems of boron in the MENA (Middle East and North Africa) region are discussed as well as technologies, current and future, for the removal of boron from seawater. The focus is placed on current RO and ion exchange methodologies using BSRs as well as the future for the AMF method. The fundamentals of each process, the effects of experimental parameters, and findings are discussed.     

水中硼的去除方法研究进展

硼广泛应用于现代工业的各个领域,随之而来的含硼废水也开始引起人们的关注。苦咸水和海水由于硼含量较高,作为饮用水或灌溉水之前必须进行除硼处理。水中硼的去除方法逐渐成为人们关注和研究的热点之一。概述了硼的相关环境标准及水中硼的去除方法,分析了各种方法的优缺点,探讨了除硼方法的发展趋势。     

硅质材料中硼含量测定方法的研究

本文建立了采用铍试剂Ⅲ分光光度法测定硅质硅质nationertometry材料中硼元素的含量的方法,该方法可用于多种硅酸盐材料中硼含量的分析,测定值符合标准要求值。通过对硅质土壤标准物质中硼含量的测定,方法具有准确度爵、检出限低、分析速度快、操作方便等优点,加标回收率95％～102％,相对标准偏差小于3．8％。     

Properties of electrodeposited nanocrystalline Ni-B alloy films

The influence of the boron content on the various properties of nanocrystalline Ni-B alloy produced by electrodeposition was investigated. The considerable reduction in grain size was observed with increasing boron content. The internal stress was tensile and increased linearly with increasing boron content. Hardness increased up to 750 Hv at 2 at.% boron and then kept the value to 11 at.% boron for as-plated Ni-B coatings.The hardness of Ni-B films increased considerably due to the intermetallic Ni₃B precipitation by the heat treatment and maximum hardness of each coating increases with boron content. Wear resistance decreased with increasing the boron content because of high friction coefficient and brittle fracture of coating with high content of boron.     

Synthesis of Cubic Boron Nitride under Relatively Lower Pressure and Lower Temperature via Chemical Reaction

In this paper, we present a new cubic boron nitride synthesis method via introduction of highly reactive nitrogen and boron atoms generated from chemical reactions as the raw materials of cubic boron nitride, so the system pressure and temperature are reduced significantly compared with the traditional phase transformation method at super high-pressure and high-temperature, and then the production cost of cubic boron nitride can be reduced greatly and the equipment service life can be extended significantly. Experiments have shown that by this method the cBN can be synthesized with high yield at pressures as low as 2.5 GPa and temperatures as low as 450°C. Compared with the conventional phase transformation method, the pressure decreases by about 50% and the temperature decreases by about 64%. Analyses have shown that the crystal structure of the cBN synthesized is perfect and the impurity content is extremely low.     

Structure and mechanical properties of boron-rich boron carbides

A series of boron-rich boron carbides are investigated to explore the effect of boron/carbon ratios on the microstructure and mechanical properties of the complex material. It has been found that excess boron substitution gives rise to expanded lattice constants, orientational asymmetry of the chain structure and distortion of the icosahedra of rhombohedra B₄C units in comparison with conventional carbon-rich boron carbides. Microstructure characterization reveals a high density of stacking faults and growth twins in boron-rich boron carbides. Nanoindentation measurements demonstrate that the hardness and modulus of boron-rich boron carbides decrease with the increase of boron content while the B_10.2C sample with the highest boron substitution shows relatively high hardness and modulus. This study suggests that the structure of single-phase covalent materials could be tailored by self-alloying for improved mechanical properties.     

前驱体转化法制备碳化硼粉体的研究进展

碳化硼材料具有优良的物理和化学性能,被广泛应用于各个领域。目前,传统的碳热还原方法生产碳化硼粉体存在温度高、产率低、环境污染重等问题。相比之下,前驱体转化法具有能耗低、工艺简便、原料易得、产品尺寸小等特点,在制备碳化硼粉体方面有明显的优势。详细介绍了前驱体转化法合成碳化硼粉体的制备过程,综述了使用不同碳源经前驱体转化法合成碳化硼粉体的最新研究进展,并展望了前驱体转化法合成碳化硼的研究方向。     

含团聚硼富燃料推进剂的能量特性及燃烧性能

用最小自由能计算程序计算了含硼富燃料推进剂的能量性能,探讨了不同压力时硼粉的质量分数对富燃料推进剂能量性能的影响,采用靶线法和化学滴定法研究了富燃料推进剂的燃烧特性和燃烧残渣中硼粉的燃烧效率。结果表明,随着硼粉含量的增加,推进剂的能量增大;大粒径的团聚硼对富燃料推进剂的燃速和压强指数影响较大,随着团聚硼含量的增加,推进剂的燃速提高;含硼富燃料推进剂中的硼粉燃烧后单质硼和硼化物的摩尔比发生了明显的变化,无定形硼粉经团聚后燃烧效率明显提高。