Research of chemical induction unit on mixing effect and chlorine saving

Rapid mixing and chlorine saving are two important problems that most drinking water industries are focus on, and this paper adopts chemical induction unit to compare with water jet injector to study what merits chemical induction unit has. The experiment chose coefficient of variability of chlorine concentration to evaluate the mix effect and used chlorine consumption to compare the two equipments. Distribution reservoir experiments show that chemical induction unit can completely mix chlorine less than 6.2 seconds and water jet injector can not completely mix in 3 minutes. Mixing pool experiments show that chemical induction unit can save chlorine compared with water jet injector, and can save more if more chlorine is consumed.

Impelling force and current challenges by chemicals in somatic cell reprogramming and expansion beyond hepatocytes

In the field of regenerative medicine,generating numerous transplantable functional cells in the laboratory setting on a large scale is a major challenge.However,the in vitro maintenance and expansion of terminally differentiated cells are challenging because of the lack of specific environmental and intercellular signal stimulations,markedly hindering their therapeutic application.Remarkably,the generation of stem/progenitor cells or functional cells with effective proliferative potential is markedly in demand for disease modeling,cell-based transplantation,and drug discovery.Despite the potent genetic manipulation of transcription factors,integration-free chemically defined approaches for the conversion of somatic cell fate have garnered considerable attention in recent years.This review aims to summarize the progress thus far and discuss the advantages,limitations,and challenges of the impact of full chemicals on the stepwise reprogramming of pluripotency,direct lineage conversion,and direct lineage expansion on somatic cells.Owing to the current chemical-mediated induction,reprogrammed pluripotent stem cells with reproducibility difficulties,and direct lineage converted cells with marked functional deficiency,it is imperative to generate the desired cell types directly by chemically inducing their potent proliferation ability through a lineagecommitted progenitor state,while upholding the maturation and engraftment capacity posttransplantation in vivo.Together with the comprehensive understanding of the mechanism of chemical drives,as well as the elucidation of specificity and commonalities,the precise manipulation of the expansion for diverse functional cell types could broaden the available cell sources and enhance the cellular function for clinical application in future.

Chemical Characterization of Auriferous Ores from the Brazilian State of Paraiba

One of the most important problems facing the gold industry is that the placer and free milling gold ores are almost terminating. Hence, the use of refractory ores has been increased during the recent years. In general, gold refractory ores occurs in various types of deposits associated with a range of minerals. Among the refractory ores, the sulfide type is the most common. The methodology employed in the mining process depends on the mode of occurrence of the ore and on the particle size, shape and degree of purity of the auriferous species. We have undertaken a mineralogical investigation of a representative sample of a complex gold mining ore collected in the municipality of Princesa Isabel, Paraiba, Brazil, using X-ray fluorescence spectrometry, X-ray diffractometry, infrared spectroscopy, inductively coupled plasma-atomic emission spectrometry and the Fire Assay. The results showed that the arsenic content of the ore was closely related to the gold content, and that the occurrence of “invisible gold” was associated primarily with pyrite and secondarily with arsenopyrite. The sulfur content of the ore was directly related to its refractoriness. It is concluded that gold mineralization in the study area is mainly of the gold-quartz-sulfide veins (lode gold), while the gold found in the mini-fractures of the deposits is probably associated with the hydrothermal processes that occurred in the region.

Subcellular Distribution and Chemical Forms of Cadmium in the Medicine Food Homology Plant Platycodon grandiflorum(Jacq.)A.DC.

Although Platycodon grandiflorum(Jacq.)A.DC.is a renowned medicine food homology plant,reports of excessive cadmium(Cd)levels are common,which affects its safety for clinical use and food consumption.To enable its Cd levels to be regulated or reduced,it is necessary to first elucidate the mechanism of Cd uptake and accumulation in the plant,in addition to its detoxification mechanisms.This present study used inductively couple plasma-mass-spectrometry to analyze the subcellular distribution and chemical forms of Cd in different tissues of P.grandiflorum.The experimental results showed that Cd was mainly accumulated in the roots[predominantly in the cell wall(50.96%-61.42%)],and it was found primarily in hypomobile and hypotoxic forms.The proportion of Cd in the soluble fraction increased after Cd exposure,and the proportion of insoluble phosphate Cd and oxalate Cd increased in roots and leaves,with a higher increase in oxalate Cd.Therefore,it is likely that root retention mechanisms,cell wall deposition,vacuole sequestration,and the formation of low mobility and low toxicity forms are tolerance strategies for Cd detoxification used by P.grandiflorum.The results of this study provide a theoretical grounding for the study of Cd accumulation and detoxification mechanisms in P.grandiflorum,and they can be used as a reference for developing Cd limits and standards for other medicine food homology plants.

Comparison of 66 chemical element contents in normal and benign hyperplastic prostate

Objective:The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia(BPH)and healthy male.Methods:We evaluated the prostatic level of 66 chemical elements in 43 patients with BPH and 37 healthy males.Measurements were performed using five instrumental analytical methods.Results:In the hyperplastic prostates,we have observed a significant increase in the mean level of Bi,Cr,Hg,K,Sb,and Se accompanied a significant decrease in the mean level of Al,Ce,Cs,Dy,Er,Gd,Ho,La,Mo,Nd,Pb,Pr,Sm,Sn,Tb,Tm,U,and Y.No differences were found in the mean prostatic level of other chemical elements including Ag,Al,Au,B,Ba,Be,Br,Ca,Cd,Co,Cu,Fe,Li,Mg,Mn,Na,Nb,Ni,P,Rb,S,Sc,Si,Th,Ti,Tl,Yb,Zn,and Zr between BPH patients and healthy males.Conclusions:The finding of chemical element contents and correlation between pairs of chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element metabolism in BPH gland.Trace elements Bi,Cr,Hg,K,Sb,and Se may be regarded as the possible tissue biomarkers of hyperplastic transformation of prostate gland.Obtained data did not confirm a critical role of Cd and Pb accumulation in the pathogenesis of BPH.A potential age-related Zn,Fe,and Se deficiency in the prostate tissue has not been found as being involved in the etiology of BPH.

Numerical Investigation of Flow Fields in Inductively Coupled Plasma Wind Tunnels

Numerical simulations of 10 kW and 110 kW inductively coupled plasma （ICP） wind tunnels were carried out to study physical properties of the flow inside the ICP torch and vacuum chamber with air as tile working gas. Two-dimensional compressible axisymmetric Navier- Stokes （N-S） equations that took into account 11 species and 49 chemical reactions of air, were solved. A heat source model was used to describe the heating phenomenon instead of solving the electromagnetic equations. In the vacuum chamber, a four-temperature model was coupled with N-S equations. Numerical results for tile 10 kW ICP wind tunnel are presented and discussed in detail as a representative case. It was found that the plasma flow in the vacuum chamber tended to be in local thermoehemical equilibrium. To study the influence of operation conditions on the flow field, simulations were carried out for different chamber pressures and/or input powers. The computational results for the above two ICP wind tunnels were compared with corresponding experimental data. The computational and experimental results agree well, therefore the flow fields of ICP wind tunnels can be clearly understood.

伟晶岩型锂矿石中锂的化学物相分析方法研究

伟晶岩型锂矿石中产出的锂云母和锂辉石是重要的提锂原料,化学物相分析能够为这类锂矿石的地质勘探、矿床评价和高效选冶等提供重要的技术支撑。由于各类含锂矿物在化学性质上非常相似,目前尚未见与锂矿石化学物相分析相关的报道。本文建立了一种针对伟晶岩型锂矿中锂进行化学物相分析的方法。将锂物相分为铁锂云母中锂、锂云母中锂和锂辉石中锂三相。采用稀盐酸选择性浸出铁锂云母中锂,浓硫酸选择性浸出锂云母中锂,最后残渣用氢氟酸挥发除硅,王水溶解测定锂辉石中锂,并探索确立了各相态的最佳浸出条件。通过对川西某锂矿中锂物相进行6次分析,得到各相态锂的相对标准偏差(RSD)为1.27%~3.79%,均小于5%,各相态锂的加和与总锂结果的相对偏差为1.22%,小于5%,说明该方法适用于伟晶岩型锂矿石中锂的化学物相分析。

农田土壤理化参数快速获取技术研究进展与展望

[目的/意义]土壤是农业基本的生产资料,其质量与农业高效生产和可持续发展密切相关。由于以往对农田的高强度利用以及土壤侵蚀等原因,导致部分农田出现土壤有机质明显下降、地力减弱和生态功能退化等现象。土壤理化参数作为揭示土壤空间特征、评估土壤肥力的关键指标,对农田可持续利用起着至关重要的作用。因此,土壤理化参数信息的快速获取极为必要。[进展]探讨了农田土壤理化参数获取技术的研究意义,总结了当前用于农田土壤理化参数信息获取的主要技术,包括以电化学分析和光谱分析为主的实验室快速检验技术,以电磁感应、探地雷达、多光谱、高光谱和热红外为主的近地快速感知技术,以直接反演法、间接反演法和结合分析法为主的卫星遥感技术,以及近年的新型快速获取技术,如生物传感、环境磁学、太赫兹光谱和伽马能谱等,梳理了各方法的优缺点及适用情况。[结论/展望]结合农田环境的作业需求,依据未来研究的侧重方向提出发展建议,包括开发便携化、智能化和经济型的近地土壤信息获取系统及设备,实现土壤信息的原位快速检测。优化低空土壤信息获取平台的性能,完善数据的解译方法;联合多因素构建卫星遥感反演模型,利用多种共享开放的云计算平台实现数据的深度挖掘。深入探索多源数据融合在土壤理化参数信息获取中的研究与应用,构建泛化能力强、可靠性高的土壤信息感知算法和模型等,从而实现土壤理化参数信息快速、精准和智能化获取。

CO_(2)与液态物质耦合对沉香形成及成分的影响

【目的】探明CO_(2)与液态物质(无机盐、激素和真菌)耦合对土沉香Aquilaria sinensis结香的诱导效果,寻求高效诱导土沉香结香的新方法,为人工诱导结香技术促进结香提供理论依据。【方法】以13年生土沉香为研究对象,采用CO_(2)与3种液态物质(无机盐、激素和真菌)耦合的方法诱导处理树体,1年后,取样观察沉香树体结香部位切片组织结构和内含物变化,并检测醇溶性挥发油含量及化学成分。【结果】1)不同诱导处理对土沉香木质部中的淀粉颗粒均有不同程度的消耗。木薄壁细胞内侵填物质通过导管–薄壁细胞间半具缘纹孔进入相邻导管内积累至完全堵塞。2)CO_(2)与3种液态物质(无机盐、激素和真菌)诱导处理中,射线薄壁细胞、轴向薄壁细胞和导管内油脂类物质积累存在差异,CK-1(只充CO_(2))仅存有少量油脂类物质,CK-2(只打孔不充CO_(2))未观察到油脂类物质。3)诱导变色范围受诱导方法影响较大,处理孔位置越远诱导变色距离越短,CO_(2)与无机盐联合诱导处理变色范围最大。4)不同诱导处理的醇溶性挥发油含量存在差异,黑褐色树脂越多含量越高。GCMS结果显示,5种诱导处理后共鉴定出74种化合物,其中共有的成分主要为11种,且部分醇溶性挥发油成分的相对含量在不同处理间差异较大。【结论】5种诱导方式所产沉香样品的醇溶性挥发油含量、沉香特征性成分及含量存在差异,CO_(2)与无机盐耦合诱导的土沉香特征性成分和含量均高于其他处理,诱导所产沉香品质最好,其次为CO_(2)与真菌联合诱导所产沉香,仅填充CO_(2)所产沉香品质较差。

‘无核白’葡萄多倍体的化学诱导及鉴定

以‘无核白’葡萄分生愈伤组织和胚性愈伤组织为外植体材料,分别通过秋水仙素与安磺灵浸渍法进行诱导,比较不同外植体材料成苗后的存活率和诱变率差异,利用流式细胞仪鉴定成苗倍性。结果显示,秋水仙素浸渍法诱导‘无核白’分生愈伤组织,分别在浓度为100 mg·L^(-1)处理48 h和250 mg·L^(-1)处理24 h获得嵌合体苗,前者诱变率为2%,后者诱变率为4%,且经组培方式纯化获得纯合四倍体;利用安磺灵浸渍法诱导‘无核白’分生愈伤组织获得了7株嵌合体苗,1.73 mg·L^(-1)处理48 h的试验组获得最高存活率为80%,1.73 mg·L^(-1)处理72 h的试验组获得最高诱变率为8.0%;采用秋水仙素浸渍法对‘无核白’胚性愈伤组织进行加倍处理,未获得成苗;采用安磺灵浸渍法对‘无核白’胚性愈伤组织进行加倍处理,当处理浓度及时间为5.19 mg·L^(-1)、24 h时,获得成苗4株,其中2株为嵌合体。

葡北油田天然气水合物化学防治技术研究

针对葡北油田开发过程中注气井和采油井生成的水合物易堵塞井筒的问题,采用动力学抑制剂防止水合物生成、热力学抑制剂解除水合物堵塞。以N-乙烯吡咯烷酮、N-乙烯己内酰胺、二甲基二烯丙基氯化铵为单体,通过自由基聚合反应合成了动力学抑制剂HI-3,评价了动力学抑制剂HI-3对水合物生成的抑制性能以及热力学抑制剂对水合物堵塞的解除效果。结果表明,在4℃、8 MPa条件下,1%HI-3抑制剂可将水合物生成的诱导时间延长至1380 min以上;热力学抑制剂对水合物分解速率的大小顺序为:乙二醇>二甘醇>丙三醇>甲醇>乙醇,且升高热力学抑制剂乙二醇的温度,可加快水合物的分解速率。

口腔癌动物模型建立的研究进展

口腔癌是头颈部恶性肿瘤中最常见的类型之一,因其位置特殊、恶性程度高,可引起口腔颌面部组织的缺损,导致语言、咀嚼和吞咽等功能丧失,严重影响患者生活质量,甚至造成死亡。研究人员建立了与人类口腔癌相似的口腔癌动物模型来研究口腔癌的病因、发展、浸润和转移机制,为口腔癌的诊疗提供依据。该文对口腔癌动物模型建立的研究进展作一综述。

差示扫描量热法测定压缩机油-引发剂混合体系半衰期

采用差示扫描量热法(DSC)和Kinetics Neo专业软件建立了相应的化学动力学模型,对超高压乙烯压缩机油-引发剂混合体系的半衰期进行了研究。建立的3步连串模型适用于压缩机油-引发剂混合体系半衰期的测定。测定结果表明,国产压缩机油+DTBP引发剂混合体系和进口压缩机油+DTBP引发剂混合体系对DTBP引发剂半衰期的影响均较小,国产压缩机油和进口压缩机油与乙烯反应介质的相容性相当。(图11表2参考文献9)

多种方法测定化肥中总镁含量的比较研究

研究建立了微波消解-电感耦合等离子体发射光谱法(ICP-OES法)以及原子吸收分光光度法(AAS法)测定化肥中镁元素含量的检测方法。分别使用新方法和国家标准GB/T 19203—2003中的传统方法,对2种复合肥料标准物质以及15种不同产地、不同镁源、不同镁含量的化肥样品进行测定。t检验结果表明微波消解法与GB/T 19203—2003中硝酸-高氯酸电热板消解法的提取结果无显著性差异;ICP-OES法、AAS法和GB/T 19203—2003中容量法的测定结果无显著性差异。ICP-OES法与AAS法的回收率、精密度均优于容量法。微波消解-ICP-OES法的标准物质回收率分别为110%、108%,6次平行测定的相对标准偏差为0.80%。微波消解-AAS法的标准物质回收率分别为109%、108%,6次平行测定的相对标准偏差为1.29%。与AAS法相比,ICP-OES法的精密度和标准曲线决定系数均更优,标准曲线线性范围更宽,且在实验过程中更加简便、环保,更适用于化肥样品的分析测定。

电感耦合等离子体原子发射光谱法测定Ti65高温钛合金中16种元素

以盐酸-氢氟酸-硝酸混合酸体系溶解样品,建立了电感耦合等离子体原子发射光谱(ICP-AES)测定Ti65钛合金中Al、Sn、Zr、Mo、Si、Ta、Nb、W 8种合金元素以及Cr、Mn、Cu、Ni、B、Y、Re、Fe 8种杂质元素含量的分析方法。考察了钛基体和共存元素对待测元素的影响以及硅标准溶液基体对Al元素测定的影响,采用基体匹配法消除了基体效应的影响,并通过合金元素匹配消除了光谱干扰。优化的仪器分析参数为高频功率1.2 kW,雾化气压力200 kPa。在优化实验条件下建立工作曲线,其线性相关系数均不小于0.9987,各元素的检出限为0.00003%~0.010%。采用该方法测定钛合金标准样品以及配制的Ti65钛合金模拟样品,实验结果与理论值相吻合。实验结果的相对标准偏差在8.6%以内,加标回收率为98.0%~104%。

45钢链轮淬火裂纹常见原因分析与预防

45钢链轮在调质处理或感应淬火时,表面时常出现淬火裂纹。对淬火裂纹产生原因进行分析,提出了预防淬火裂纹的措施。应根据链轮化学成分、原材料金相组织、链轮结构复杂程度和表面状态等进行分析,制定合理的热处理工艺,采取预防措施,减小链轮淬火时热应力和组织应力。还需要加强现场工艺操作管理,增强责任心,避免45钢链轮淬火裂纹产生。

光电探测技术在化工厂有害物质的检测与定量分析中的应用

为提高传统化工厂重金属检测技术的准度及精度,研究将光电探测技术中的原子吸收法与电感耦合等离子体-发射光谱法联合,用于测定有害物质的含量。发现研究提出的联合光电探测技术的最大误差不超过0.03μg/L,且联合光电探测技术的最大相对标准误差不超过0.3μg/L。综上结果可知,研究提出的两项光电探测技术对重金属有害物质检测及定性分析具有一定的可信性及可靠性,故该方法在化工厂中检测与定量分析重金属有害物质方面具有良好的应用前景。

船用低速柴油机十字头表面感应淬火裂纹分析

船用大型低速柴油机十字头是很重要的运动部件,由于其润滑条件恶劣,所以容易发生损坏。在对5S50MEB#20主机的十字头成品进行磁粉检测时,发现裂纹。通过采用硬度检测、裂纹宏观分析、金相组织检验、化学成分分析等方法,对十字头出现裂纹的原因进行了分析。结果表明:裂纹性质为淬火裂纹,是在中频感应加热淬火过程中,因局部拉应力集中造成的。通过改进热处理工艺,将加热方式改为旋转加热,避免了裂纹的产生。

秋水仙素对蝴蝶兰试管苗叶切片胚状体发生期的化学诱变

【目的】以蝴蝶兰试管苗叶片为材料诱导多倍体。【方法】用不同浓度的秋水仙素,对蝴蝶兰试管苗离体叶片进行诱变处理,考察不同处理时间类原球茎形成及苗再生的效应,比较二倍体和多倍体试管苗的形态特征、叶片下表皮组织细胞结构特征,并对多倍体根尖细胞染色体数进行鉴定。【结论】秋水仙素对蝴蝶兰离体叶片类原球茎的形成及其再生苗产生较大影响,较高浓度的秋水仙素处理时间较长,形成类原球茎的叶片比率及再生苗数减少明显,但多倍体形成的比率相对较高。多倍体苗叶片表面粗糙、叶片厚实、植株较矮,生根数少而粗短。叶片下表皮组织细胞、气孔结构与二倍体差异大,细胞核明显较大,染色体加倍。

文心兰多倍体诱导及其鉴定

以类原球茎薄切片为外植体,用秋水仙素对离体薄切片再生类原球茎过程进行多倍体诱导,建立文心兰多倍体离体化学诱变技术体系。探讨了不同浓度的秋水仙素在不同诱变时间内对离体薄切片类原球茎形成及苗再生的诱变效应,比较了二倍体和多倍体试管苗的形态特征、叶片下表皮组织细胞结构特征,并对多倍体根尖细胞染色体数进行了鉴定。结果表明,秋水仙素对文心兰离体薄切片类原球茎的形成及其再生苗产生较大影响,较高浓度的秋水仙素处理较长时间时,形成类原球茎的薄切片比率及再生苗数减少明显,但多倍体形成的比率相对较高;多倍体苗叶片厚实、紧凑、植株较矮;叶片下表皮组织细胞、气孔结构与二倍体存在一定差异,细胞核明显较大,染色体加倍成功。