Synthesis,characterization,and antimicrobial properties of Cu-inorganic antibacterial material containing lanthanum

In this paper a kind of new inorganic antibacterial material:Cu-antibacterial white carbon black containing lanthanum was synthesized.The characterization and antimicrobial effect of the Cu-antibacterial white carbon black containing lanthanum was investigated.Inorganic antibiotic materials comprised the carrier,the antibacterial ion and the additive.In this study,we choosed white carbon black as the carrier,which was compound by a sol-gel method.Copper ion was selected to be the antibacterial ion,and lanthanum nitrate was selected to be the additive.The as-synthesized Cu-La-antibacterial white carbon black was characterized by inductively coupled plasma(ICP),laser particle size analyzer,Fourier transform infra-red spectroscopy(FT-IR) and antibacterial activity test(Escherichia coli as experimental bacterium).Results showed that the amount of antibacterial ions of the Cu-La-antibacterial white carbon black was higher than that for the general Cu-antibacterial white carbon black.Its bacteriostasis rate was about 98%(when the content of Cu2+ was about 3%),and corresponded to Ag-antibacterial white carbon black(99%).The particle size of Cu-La-antibacterial white carbon black was under 30 μm with a narrow size distribution.Copper ion was bound to white carbon black by ion exchange process.Moreover,this new inorganic antibacterial material showed promising result on the coating surface of metal.     

Optimized preparation of zinc-inorganic antibacterial material containing samarium using response surface methodology

A Box-Behnken design(BBD) of response surface methodology(RSM) was used to optimize the preparation of the Zn-Sm antibacterial white carbon black by the sol-gel method. The statistical analysis of the results showed that the particle size of the Zn-Sm antibacterial white carbon black was significantly affected by the reaction time, reaction temperature and the stirring speed. According to analysis of variance(ANOVA), the values of the determination coefficient(R2=0.9821) and the "Pred R-Squared" of 0.8227 were in reasonable agreement with the "Adj R-Squared" of 0.9591. It was indicated that this model could be used to navigate the design space. The optimized reaction time, temperature and the stirring speed were 0.88 h, 87.83 oC, and 473.45 r/min, respectively. In addition, the bacteriostasis rate of the product was about 97.92%.     

Synthesis,characteristics, and antibacterial activity of a rare-earth samarium/silver/titanium dioxide inorganic nanomaterials

An inorganic nanomaterials combination of Sm, Ag, and TiO2 was synthesized using supercritical fluid drying （SCFD） combined with solgel techniques. The structure, photocatalysis and bacteriostatic activity of the materials were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, X-ray photoelectron spectroscopy （XRPS）, photocatalytic performance, and antibacterial activity experiments. The XRD results showed that the average particle diameter of Sm/Ag/TiO2 was 14.62 nm and Ag and Sm ions were dispersed on the surface of TiO2 in a highly dispersed, amorphous form. The TEM image showed that the size of the particle was 12 nm using the scherer formula. The XPS result showed that the element Sm was doped and Ag was loaded inorganic nanomaterials successfully. Sm/Ag/TiO2 exhibited optimal photocatalytic properties at 600 oC, the photocatalytic optimal proportion of Sm/Ag/TiO2 was 2：2：100. When the molar ratio was 2：2：100, the bacteriostatic circle diameter was 16 mm for Staphylococcus aureus, the minimum bacteriostatic concentration was 200μg/mL for white beads coccus, and the minimum bactericidal concentration was 2×10^4μg/mL for white beads coccus. The SEM results showed that the antibacterial material attached to the candida albicans cell surface, cells appeared fold deformation. Therefore the inorganic nanomaterials Sm/Ag/TiO2 had high temperature resistance, good photocatalytic and antibacterial characteristics in visible light.     

Antibacterial Characteristics of ZnO-CeO2 Nano-Powder Prepared by Laser Vapor Condensation

Microbialpollutionandcontaminationbymicroor ganismshaveproducedvarioustroublesinindustryandothervitalfields ,suchasdegradationandinfec tion .Thenewpasteurizationandantibacterialtech niqueshavebeendemandedandstudied[1] .Inrecentyears ,therareearthmetaloxid…     

载银纳米SiO2制备与抗菌性研究

在60%硫酸乙酯催化下TEOS水解,通过控制水解条件,得到担载体纳米SiO2。采用吸附法在其表面负载银,制备无机抗菌材料。用抑菌圈直径和杀菌率表征粉末抗菌性能,研究了吸附时间、硝酸银浓度及吸附温度与负载量的关系,并考查了焙烧温度等因素对抗菌性能的影响。研究发现,以离子形式存在的贵金属银的抗菌性能强,焙烧处理温度决定其离子溶出性与可重复使用次数。     

无机包膜过程中铝离子的行为规律分析

针对钛白粉无机包膜中铝离子的沉积规律,通过分光光度法确定了不同铝盐的沉积pH值范围,并采用在线颗粒检测仪对铝离子沉积过程中粒子的数量及粒度进行了实时监测,同时利用FTIR、SEM及XRD对不同沉积条件所得的固体物质进行了分析,确定了不同酸度条件得到的沉淀物的特性,为钛白无机包膜提供参考。     

菱镁矿煅烧制备氧化镁及其活性检测的研究进展

氧化镁是一种重要且需求很大的无机化工原料,是制备高附加值镁质产品的原材料,其来源之一就是由菱镁矿经过高温煅烧获取。通过控制菱镁矿颗粒的粒径、煅烧方式、是否掺入添加剂、菱镁矿内部组分杂质含量、新的煅烧工艺等来优化煅烧流程,最终制取高活性的氧化镁产品。另外,氧化镁的制备与活性检测是分不开的,从菱镁矿的煅烧方式,以及氧化镁活性检测两方面进行了综述,对其工艺的改进提出了展望与建议。     

热轧H13钢硬度不均匀性的分析

 对H13钢试样进行了退火试验,对退火前后试样进行了硬度测试及扫描电镜和能谱分析。分析了H13钢热轧材硬度不均匀性的形成原因。结果表明,低倍“黑斑”区域硬度平均值为91.43HRB,比正常区域高7.53%;“黑斑”区域主要由“白斑”和“黑色质点”组成,“白斑”化学成分主要是铁,“黑色质点”主要成分为合金碳化物;H13钢试样经退火后,原“黑斑”区域硬度明显降低,从190.2HB下降到168.26HB,退火后“黑色质点”尺寸变小,其碳质量分数大幅度降低,从80%下降到15%;H13钢热轧材硬度不均匀主要是由于钢液凝固过程中成分不均匀所致。     

原料粉末对制备碳化钒的影响

为工业化生产提供实验室研究基础,本文以V2O5和纳米碳黑为原料,利用碳热还原法,在常压下碳管炉中得到了V8C7粉末。通过X射线衍射仪(XRD)、扫描电镜(SEM),分析了原料对反应进程的影响。结果表明:采用普通球磨干混的方式时,比表面积(BET)为112m2/g的碳黑可以加速反应进程,过低或过高都不利于反应的进行;细粒径的V2O5原始粉末可明显加快反应进程,最终得到大小均匀,粒度1μm以下的球形碳化钒粉末。反应机理研究表明,固-固反应的速率与反应组元的颗粒大小和混合均匀程度,以及不同反应组元之间的接触面积有很大关系。     

还原碳化法制备超细碳化铬粉末

以纳米Cr_2O_3和乙炔黑为原料,经高温还原碳化制备超细Cr_3C_2粉末,研究反应温度、反应时间以及配碳量对Cr_3C_2粉末的粒度与游离碳含量的影响。通过热力学计算,只有当温度高于1 350 K时还原碳化反应才有可能进行,采用纳米Cr_2O_3可显著降低反应温度,在1 573 K下焙烧6 h碳化率即达到98.20%;Cr_3C_2粉末的游离碳含量随配碳量增加而显著提高,配碳量(质量分数)为理论配碳量的1.05倍时制得游离碳含量为0.23%、氧含量为0.91%(均为质量分数)、平均粒度为1μm的Cr_3C_2粉末,该粉末达到硬质合金及热喷涂应用的要求。     

高温焙烧法处理铝电解废旧阴极炭块

废旧阴极炭块的无害化与资源化已成为制约铝电解行业绿色可持续发展的资源环境难题。利用高温焙烧法处理废旧阴极炭块,基于不同粒度废旧阴极炭块的工业成分和浸出毒性,探索骨料粒度和焙烧温度对高温焙烧处理效果的影响。结果表明,随着骨料粒度的增大和焙烧温度的提高,回收炭材料碳含量逐渐提高,可溶性氟化物含量大幅降低。在最佳高温焙烧参数下,回收炭材料的碳含量由65.21%提高至94.52%,F^-浸出浓度由4 018.55 mg/L降至7.63 mg/L。同时利用化学沉淀法对气态冷凝产物进行固化处理,提取高纯度的CaF₂产品,避免高浓度含氟烟气二次污染。通过高温焙烧法处理铝电解废旧阴极炭块具备技术可行性。     

钨粉和碳黑粉粒度对超细WC粉质量的影响

本文采用不同粒度的超细钨粉 (费氏粒度 :0 38、0 41、0 43、0 80、3 6 0、4 5 0、4 5 0 μm)与多种不同粒度的碳黑粉 (费氏粒度 :0 1、0 3、0 5、0 8、4 3、5 3μm)混合 ,在常规碳化工艺 (W +C =WC)条件下 ,( 830～ 1 5 6 0℃ )较宽碳化温度区间内 ,研究了钨粉粒度、碳黑粉粒度对所制备的WC粉的化合碳含量、粒度的影响。在试验中通过化学分析法 ,XRD分析测定WC粉的化合碳、游离碳含量及产物的物相组成 ,并用BET和费氏法测量WC粉的粒度。结果表明 :当采用超细碳黑 (粒度≤ 0 1 μm)时 ,随着W粉粒度变粗 (费氏粒度 0 38～ 4 5 μm)所得WC粉粒度由 0 5 7μm增大到 4 75 μm。碳黑粉粒度对WC粉粒度没有明显影响 ,但碳黑粉粒度对碳化温度、WC粉的化合碳含量、物相组成 ,即WC粉的整体质量影响大     

谈质材料对结晶器保护渣熔融特性的影响

 连铸过程通常采用调节配炭量和配炭方式来调节保护渣的熔化速度和熔融层状结构。本文通过单向加热炉模拟保护渣在结晶器内的熔化过程，研究了六种炭质材料对保护渣熔化速度和熔融结构的影响。结果表明：含量相同时对保护渣熔化速度的控制作用最强的是500目超细石墨，而后依次是：半补强炭黑、390石墨、中超炭黑、土状石墨、增碳剂；配炭方式相同时，保护渣的熔化温度越高，其熔化速度越慢；采用炭黑加石墨的配炭方式时保护渣的烧结层厚度随炭含量增加而减薄，且若炭黑量小于2%时形成多层熔融结构，否则将形成不含半熔层的三层结构。     

铜尾矿库尾矿全粒径规模化低碳消纳研究

某大型矿冶集团针对该集团铜尾矿库尾矿大量堆存,安全环境风险突出,新建尾矿库选址困难、尾矿消纳途径有限等问题,通过长期摸索研究和对铜尾矿库尾矿粒径分布、成分、化学属性、浸出毒性和放射性等因素进行分析,探索出通过胶凝改造技术充填、制备公路工程无机结合料和铜尾矿资源脱硫分级综合利用的低碳材料消纳模式,尾矿库尾砂能够全粒径规模化消纳利用。单位产品分别消纳尾矿0.075t/t、0.1275 t/t和1t/t,降碳1.564t/t、0.054t/t和0.5195t/t,并分别具有40.0971元/t、12.1235元/t和14.4653元/t的环境正效益,同时协同处置了大量其他固体废物,真正实现了铜尾矿全粒径规模化增值消纳,在全国范围内有很好的借鉴意义。     

Particle Size and Clogging of Granular Media Permeated with Leachate

The effect of particle size (4-, 6-, and 15-mm nominal sizes) on the rate of clogging of columns of porous media permeated with municipal solid-waste leachate is examined. Clogging is shown to be more localized over a small volume of the porous media near the influent end of the column for smaller particles than for larger particles, where clogging was more uniformly distributed along the column. This is attributed to the greater surface area per unit volume of smaller particles allowing greater biofilm growth per unit volume. This increased the reduction in chemical oxygen demand (COD) and caused greater deposition of inorganic clog material per unit length of column than for larger particles. The distribution of methanogenic bacteria was found to closely correspond to the zones of most severe clogging. The bulk density of clog material is shown to be between 1.6 and 1.8 Mg∕m3. The chemical composition of the clog material is essentially independent of particle size, with calcium representing 26% of the dry mass of the clog material and CaCO3 being the main component of the clog. An examination of the yield of CaCO3 relative to COD indicates that the carbon in the CaCO3 represents <4% of the organic carbon represented by the drop in COD. Finally, the data from the column test is used to predict the expected time to clog for an actual landfill and were found to give results consistent with what was observed in the field.     

新型炭素材料对滑板性能的影响

通过对超细石墨、纳米炭黑等滑板用新型炭素材料的实验研究,发现不同粒度的石墨对铝锆碳滑板的热震稳定性影响不同;纳米级炭黑对滑板的成型性能、抗氧化性能、热处理后β-SiC的生成量等都能产生很大的影响。选择超细石墨和粒度为26~30 nm的炭黑按照一定比例添加制成的新型滑板使用效果很好。     

稀土壳聚糖配合物的制备、表征和抑菌性能研究

以天然高分子壳聚糖和稀土硝酸盐为原料,室温下,壳聚糖与稀土硝酸盐溶液在稀醋酸中反应,制得一系列新型稀土壳聚糖配合物.通过红外光谱、X射线能谱、差热-热重、X射线光电子能谱、透射电镜等对合成物进行分析、表征.所合成的配合物由分散的纳米粒子组成.并采用培养基扩散法、营养肉汤稀释法等抑菌实验方法对其进行了抑菌活性研究,结果表明其对大肠杆菌和金黄色葡萄球菌均有很好的抑菌作用,最小抑菌浓度(MIC)在200μg·mL~(-1)～300μg·mL~(-1)范围内,低于800μg·mL~(-1),且抑菌效果明显优于单独的壳聚糖、稀土硝酸盐.     

原料粒度分布对沸腾氯化工艺的影响

在沸腾氯化生产过程中,原料粒度、配碳比、反应温度和气流速度等是影响沸腾氯化效果的主要因素,而原料粒度及其分布是其中最重要的影响因素。原料的最小粒径应大于氯化过程中飘逸出炉体的最大颗粒粒径,最大粒径应小于现有载气压力能够浮起的最大颗粒粒径。从化学动力学和流体动力学两个角度计算气流速度和原料粒度匹配,并通过生产实践中的数据分析进行粒度范围修正,总结出与沸腾氯化设备结构相匹配的原料粒度分布范围。     

Influence of Composite Phosphate Inorganic Antibacterial Materials Containing Rare Earth on Activated Water Property of Ceramics

Antibacterial ceramic was prepared by doping enamel slurry with composite phosphate inorganic antibacterial materials containing rare earth (inorganic antibacterial additives), and then the mechanisms for activating water and improving seed germinative property were tested by nuclear magnetic resonance (NMR) and the method of testing oxygen dissolved in activated water. Results show that the half peak width of ^17O-NMR for tap water activated by the antibacterial ceramic drops from 115.36 to 99.15Hz, and oxygen concentrations of activated water increase by 20%, germinate rate of horsebean and earthnut seeds increases by 12.5% and 7.5%, respectively. Therefore antibacterial ceramic doped enamel slurry with inorganic antibacterial additives containing rare earth can reduce the volume of clusters of water molecules, improve activation of tap water, and promote plant seeds germinate.     

Green synthesis of ceria powders with special physical properties by carbon dioxide carbonization

In order to improve the application values of Ce element, in this paper, rare earth chloride solution was used as raw material, the pH value was controlled by inorganic alkali, the ceria powders with special physical properties were prepared by carbon dioxide carbonization method. According to characterization of SEM, XRD, and TG-DSC, Ce(OH)3 prepared at pH = 7.5 exhibits smaller particle size than that prepared at other conditions. CeO_2 precursor obtained by direct carbonization of Ce(OH)3 shows smaller particle size and narrow size distribution, CeO_2 precursor forms at first by carbonization of Ce(OH)3 with the continuous addition of CO2 gas,and the chemical component is indicated to be Ce_2 O(CO_3)_2·6 H_2 O.Cubic phase CeO_2 powders are obtained by calcined at 750 ℃ for 4 h. The mean particle size D_(50) is0.941 μm, and particle size distribution is smaller than 1. The microscopic appearance is homogeneous,with a spherical-like shape and a grain size of 200-500 nm. The light quality characteristics of sedimentation volume and accumulation density are obviously better than those of carbonate precipitation products. The carbonization method can be used not only to obtain ultra-fine rare earth oxides with fine particle size, narrow distribution and high dispersion properties, but also to achieve the reuse of carbon dioxide greenhouse gas.