X射线能谱研究鞣性金属在绵羊皮革中的分布

以绵羊皮革为研究对象,利用X射线能谱仪(EDXA)分析了鞣性金属锆铬在绵羊皮革中的分布,结果表明:鞣性金属元素锆、铬在绵羊皮革中的分布整体上比较均匀,但局部存在不均匀现象,鞣性金属组分主要分布于纤维束边缘,纤维束的空隙和内部含量均较低.     

ICP-AES测定铝-钛-硼合金中的16种元素

电感耦合等离子体-原子发射光谱法(ICP-AES)测定铝-钛-硼合金中钛、硼、铁、硅、镓、铜、锶、锆、锌、镁、锰、镍、铅、钒、镉和铬等16种元素含量.对分析线的选择、铝基体的干扰,样品的预处理过程进行了探讨.经实验,方法的回收率在95%-110%之间,测定结果的相对标准偏差(n=6)在0.4%-3.0%之间.该方法准确...     

空气－乙炔火焰原子吸收测定铬时某些化学干扰的计算消除方法

本文研究了空气－乙炔火焰原子吸收法测定铬时某些化学干扰的计算消除方法，用多项式作为表达铬和干扰元素间相互关系的函数式。经测定钴－钛，铬－铁和铬－钒干扰对混合液中铬的含量，表明计算法能较好地消除铁、钴、钒对测铬的干扰效应。     

发射光谱法测定乳浊料中的锆和铪

研究了用碳粉和二氧化钛作缓冲剂同时测定乳浊料中的锆和铪的发射光谱法,选择钛作内标线,不需分离、不需化学处理,直接压样于杯形的石墨电极中,具有简便、快速、准确的特点。对测定条件、干扰因素进行了研究,从而建立测定锆和铪的新方法。锆和铪的分析线分别为327.3和286.6 nm,内标线选择为钛的308.8 nm线,锆和铪的线性范围分别为0～0.50%和0～0.25%。锆和铪的检测限分别为0.001%和0.010%,其回收率为96.67%～105.0%,当n=9时,锆的RSD为3.61%;铪的RSD为4.82%;用于样品的测定取得了满意的结果。     

铝合金的看谱分析

利用配有电弧和火花光源的看谱镜，分析铝合金中各元素。根据铝合金中各种含量不同元素的规律性，找出看谱分析各元素的先后顺序为：铜、镁、锌、锰、钛、铬、镍、钒、铁、硅等元素，在这些元素中，铜、镁、硅、锰作定量、半定量分析，其余元素作定性分析，即能较准确、迅速、顺利地定出铝合金的各种牌号。     

ICP固体粉末法在化探扫面开发性试验上的应用

以ICP固体粉末法作区域化探扫面的测试,在开发性试验上已获得较好的效果。分析了1493个样品。图边样品141个,一级监控样24个,二级监控样156个,重复分析样76个,批间内检样64个,自检样39个,总计1993个样品。所得的结果满足了化探测试的要求。一次取样同时测定硼、钡、铍、铬、镧、铌、锶、钛、钒、钴、钇及锆等十二个元素。一、仪器装置     

两种典型耕作土壤粘粒矿物XRD光谱特性分析

以东北粮食主产区典型耕作黑土和黑钙土为研究对象,在测定同一气候和地理位置下两种耕作土壤颗粒组成特征情况的基础上,采用X射线衍射(XRD)分析方法,对两种耕作土壤的粘粒矿物组成及相关差异进行分析,深入探讨其内在变化机理,是土壤矿物研究的新视角。结果表明：两种供试土壤颗粒组成均以砂粒为主,粘粒、粉粒次之;当颗粒累积率达到50%时,中央粒径分布在15～130 μm区间,除胜利乡黑土剖面外,各采样地两类土壤的剖面中粘粒含量的分布顺序呈现出与中央粒径大小相反的趋势。土壤粘粒在两种土壤剖面中呈现不同的分布规律,黑土剖面中粘粒在表层富集(18.82%),而黑钙土剖面中在钙积层富集(17.41%)。除泉眼岭黑土剖面外,其余采样地的土壤剖面中粘粒含量均在母质层中最少。XRD图谱分析显示,不同土壤中粘粒矿物图谱的差异不仅表现在衍射峰的强度及部分衍射峰位的变化上,还表现在矿物组成上。黑土、黑钙土均以2∶1型粘粒矿物为主,黑土组成为蒙伊混层-伊利石-蛭石型,黑钙土为蒙伊混层-伊利石-蒙脱石型,且均含有少量的高岭石、绿泥石、石英等原生矿物。     

浙产竹叶椒不同部位挥发性成分的GC-MS分析比较

分析浙产竹叶椒不同部位的挥发性化学成分.用水蒸气蒸馏法提取挥发性成分,采用气相色谱-质谱联用法(GC-MS)测试,并用面积归一化法计算出各组分的相对百分含量.通过计算机自动检索,从浙产竹叶椒叶、茎皮和果实中分离鉴定出的组分数分别为60、16和12.浙产竹叶椒叶、茎皮和果实3个部位的挥发性成分及含量存在很大的区别,可为进...     

决明子生芽转化有机铬的效果研究

利用透析方法将不同时间点收获的富铬决明子芽中的有机铬和无机铬分开,用石墨炉原子吸收分光光度法测定富铬决明子芽中的总铬含量和无机铬含量,计算出各时间点收获的决明子芽的有机铬转化率.探讨决明子生芽转化有机铬的效果.培育时间对决明子芽有机铬转化率有一定影响,在本实验条件下,72h是培育富铬决明子的适宜时间段.     

ICP-AES法测定六氟磷酸锂中21种杂质元素

在干燥气氛中准确称取1 g(精确至0.000 1 g)的LiPF₆样品,并用适量的碳酸二甲酯(DMC)进行溶解,再经过适当的处理后,用ICP-AES仪测定样品溶液中铍、铜、铅、钙、锆、钴、镁、钒、钛、钼、镍、锰、锶、锌、钾、铝、钡、镉、铁、铬、钠等21种杂质元素的含量。结果表明,21种元素的检出限在0.106～7.290 ng·mL-1之间,加标回收率为93.3%～102.1%,11次测定的RSD小于3.56%。方法操作方便,分析速度快,结果准确。方法已用于LiPF₆生产厂家的产品分析,完全满足要求。     

Ultrasound assisted chrome tanning: Towards a clean leather production technology

Nowadays, there is a growing demand for a cleaner, but still effective alternative for production processes like in the leather industry. Ultrasound (US) assisted processing of leather might be promising in this sense. In the present paper, the use of US in the conventional chrome tanning process has been studied at different pH, temperature, tanning time, chrome dose and US exposure time by exposing the skin before tanning and during tanning operation. Both prior exposure of the skin to US and US during tanning improves the chrome uptake and reduces the shrinkage significantly. Prior exposure of the skin to US increase the chrome uptake by 13.8% or reduces the chrome dose from 8% to 5% (% based on skin weight) and shorten the process time by half while US during tanning increases the chrome uptake by 28.5% or reduces the chrome dose from 8% to 4% (half) and the tanning time to one third compared to the control without US. Concomitantly, the resulting leather quality (measured as skin shrinkage) improved from 5.2% to 3.2% shrinkage in the skin exposed to US prior tanning and to 1.3% in the skin exposed to US during the tanning experiment. This study confirms that US chrome tanning is an effective and eco-friendly tanning process which can produce a better quality leather product in a shorter process time with a lower chromium dose.     

常见皮革的近红外光谱快速判别分析

皮革种类的鉴定对生产控制、贸易过程和市场管理都具有重要意义,目前尚未有皮革种类鉴定的正式检测标准,皮革种类鉴定主要依靠感官法、燃烧法、化学溶解法、显微镜法等综合判定,对人员要求高,主观性强。利用近红外光谱技术对市场五种常见皮革样品(头层牛皮革、剖层移膜革、羊皮革、再生革和人造革)进行分析,利用判别分析法(discriminant analysis, DA)结合标准正态变量变换(multiplicative signal correction,MSC)、多元散射校正(standard normal variate,SNV)、一阶微分(first derivative)、二阶微分(second derivative)等光谱预处理方法进行分类鉴别。结果显示：上述五种革类在同一空间中重叠严重,但是利用样本反面光谱数据可以轻易将人造革和其他革类进行区分,误判率为1.2%,余下四种天然或加工革类重叠稍显严重,在同一个空间内同时对四种革类区分效果不是很理想,两两分组的分类效果较好,误判率13%～17.9%。而不同的数据处理方法在不同的判别分析模型中带来的效果也不尽相同,未发现一种能持续稳定为模型提供优化效果的预处理手段。上述数据说明采用近红外手段对于皮革种类进行判别是具有可行性的,由于本次取样来自于市场上的皮包、皮衣、皮带等最终产品,已经过染色、压花、覆膜等各种复杂处理,可能对模型带来一定的影响,如果能采取一些手段,如扩大样本量等,减弱这些影响,应该能得到更满意的结果。     

Ultrasonic effects on titanium tanning of leather

The effects of ultrasound on titanium tanning of leather were investigated. Either 20 or 40 kHz ultrasound was applied to the titanium tanning of pigskins. Five different treatment conditions were carried out and the effects were examined, such as leather shrinkage temperature (T(s)), titanium content and titanium distribution in the leather. Overall heat loading was carefully controlled. Results showed that 20 kHz ultrasound effectively improves titanium agent penetration into the hide and increases the leather's shrinkage temperature. Doubling the frequency to 40 kHz produced negligible enhancements. An impressive 105.6 degrees C T(s) was achieved using 20 kHz ultrasound pretreatment of the tanning liquor followed by 20 kHz ultrasound in the tanning mixture (liquor plus pigskins) in a special salt-free medium. Finally, using a unique ultrasonic tanning drum with 26.5 kHz ultrasound, the T(s) reached a record level of 106.5 degrees C, a value not achieved in conventional (no ultrasound) titanium tanning. The ultrasonic effects on titanium tanning of leather are judged to make a superior mineral tanned leather.     

Sono-leather technology with ultrasound: a boon for unit operations in leather processing - review of our research work at Central Leather Research Institute (CLRI), India

Ultrasound is a sound wave with a frequency above the human audible range of 16Hz to 16kHz. In recent years, numerous unit operations involving physical as well as chemical processes are reported to have been enhanced by ultrasonic irradiation. There have been benefits such as improvement in process efficiency, process time reduction, performing the processes under milder conditions and avoiding the use of some toxic chemicals to achieve cleaner processing. These could be a better way of augmentation for the processes as an advanced technique. The important point here is that ultrasonic irradiation is physical method activation rather than using chemical entities. Detailed studies have been made in the unit operations related to leather such as diffusion rate enhancement through porous leather matrix, cleaning, degreasing, tanning, dyeing, fatliquoring, oil-water emulsification process and solid-liquid tannin extraction from vegetable tanning materials as well as in precipitation reaction in wastewater treatment. The fundamental mechanism involved in these processes is ultrasonic cavitation in liquid media. In addition to this there also exist some process specific mechanisms for the enhancement of the processes. For instance, possible real-time reversible pore-size changes during ultrasound propagation through skin/leather matrix could be a reason for diffusion rate enhancement in leather processing as reported for the first time. Exhaustive scientific research work has been carried out in this area by our group working in Chemical Engineering Division of CLRI and most of these benefits have been proven with publications in valued peer-reviewed international journals. The overall results indicate that about 2-5-fold increase in the process efficiency due to ultrasound under the given process conditions for various unit operations with additional benefits. Scale-up studies are underway for converting these concepts in to a real viable larger scale operation. In the present paper, summary of our research findings from employing this technique in various unit operations such as cleaning, diffusion, emulsification, particle-size reduction, solid-liquid leaching (tannin and natural dye extraction) as well as precipitation has been presented.     

“油青种”翡翠的矿物学特征及颜色成因

采用X射线衍射、红外吸收光谱及扫描电镜等现代测试方法,对“油青种”翡翠的矿物学特征及颜色成因进行了深入研究。X射线衍射分析结果显示,“油青种”翡翠“肉”的矿物组成为较纯的硬玉,而“皮”由硬玉、绿泥石及纤蛇纹石等三种矿物组成。红外吸收光谱分析所揭示的矿物组成与X射线衍射较为一致,同时发现“油青种”翡翠“肉”及“皮”具有~2 956,~2 919和~2 850 cm-1等三个典型有机质的特征吸收峰。“油青种”翡翠“肉”中硬玉呈现明显的柱状,结晶程度明显好于“皮”中的硬玉,但“皮”中硬玉比“肉”中硬玉明显富含Mg,说明“皮”中硬玉发生过强烈的水/岩反应。纤蛇纹石仅在“油青种”翡翠的“皮”中出现,晶面呈现明显的弯曲状。在“油青种”翡翠“肉”的裂隙处及“皮”中均发现片状绿泥石的存在,可能为“油青种”翡翠致色的主要原因。形成于还原性水/岩反应的绿泥石,会吸附或者包裹一定量的有机质,导致“油青种”翡翠出现有机质的特征吸收峰。     

一种皮革产品的红外无损检验

基于红外光谱法可以对不同形态物质进行结构分析,可对皮革产品进行定性分析。依据红外光谱谱带的数目、位置、形状和强度都随化合物不同而各不相同的特点,将牛皮革、羊皮革和聚氯乙烯（PVC）革的红外谱图进行比对和剖析,并用于皮革产品的检验。通过实验得出,利用红外方法可以快速对皮革产品进行红外无损检验。     

Mg-Zr合金微观组织电子结构研究

用递归法计算了α-Mg与α-Zr的结构能、原子结合能,Mg/Zr界面能与Mg的表面能,Mg中Zr及Zr中Fe,Mn,Si,H等杂质原子相互作用能,Mg,Zr原子态密度及其在合金中的电荷变化. 计算发现,在晶体中与Mg态密度差别很大的Zr在Mg/Zr界面却与Mg趋于相近,从而界面电子环境与Mg相似,为Mg形核生长提供有利条件;α-Zr的结构能、原子结合能低于相应的α-Mg,且Mg/Zr界面能低于Mg的表面能,从能量角度合理解释了Zr先于Mg从Mg熔体析出,并作为异质核心细化Mg晶粒的实验现象. 原子相互作用 关键词： 电子结构 晶粒细化 Mg合金     

Mg合金晶粒细化机理的电子理论研究

采用递归法计算了α-Mg与α-Zr的结构能、原子结合能,Mg/Zr界面能与Mg/液态Mg界面能,Mg中Zr及Zr中Fe,Mn,Si等杂质原子相互作用能.计算发现α-Zr的结构能、原子结合能低于相应的α-Mg,且Mg/Zr界面能低于Mg/液态Mg界面能,从能量角度合理解释了Zr先于Mg从Mg熔体析出,并作为异质核心细化Mg晶粒的实验现象.原子相互作用能的计算结果显示,Zr在Mg中相互吸引形成团簇,并与杂质形成化合物,削弱晶粒细化效果. 关键词： 电子结构 晶粒细化 Mg合金     

TEM studies of the effects of Zr additions on some HDDR-processed, high boron, NdFeB-type powders and hot-pressed magnets

The transmission electron microscope has been used to study the physical and magnetic microstructures of two HDDR-processed NdFeB-type alloys, one without Zr and the other containing 1.1 at% Zr. Studies were made of the as-produced powders and the solids produced following hot-pressing at 900°C. In the HDDR powders, the principal effects of adding Zr were to reduce the average grain size by and made the grain size distribution more uniform. In the hot-pressed samples, the effect of Zr was more dramatic in that grain growth was very significantly reduced. Zr-containing phases were identified and a simple model, due to Zener, used to provide a plausible explanation of how the small amount of Zr present could stabilise the grain size to ≈0.5 μm. The microstructural results correlated well with measured magnetic properties.