4A和13X分子筛去除水中重金属Cd~(2+)及其吸附性能研究

以4A和13X分子筛为吸附材料,考察废水pH值和Cd2+初始浓度等对Cd2+去除率的影响,并研究了分子筛对Cd2+的吸附性能。结果表明,4A和13X分子筛投加量为0.16g/L、废水pH值为5、Cd2+浓度为20mg/L时,Cd2+去除率达到95%以上;分子筛对Cd2+的去除机理以离子交换吸附为主,交换出来的Na+与分子筛吸附的Cd2+摩尔浓度比为2;在吸附热力学和动力学方面,4A和13X分子筛均符合Langmuir吸附等温模型和Lagergren二级速率方程,计算的饱和吸附容量Q0分别为150.15、163.67 mg/g,二级反应速率常数K2分别为2.45×10-3、3.96×10-4 g/(mg·s)。该吸附反应是一种单分子层反应速度较快的化学吸附过程。     

镍渣表面理化特性及对Pb2+、Cu2+的吸附研究

利用多种表征手段对镍渣的组成和表面特性进行分析,证实了镍渣具备吸附废水中重金属的能力。本实验所采用的水淬二次镍渣中含有含量较高的SiO₂、Al₂O₃、CaO、MgO等活性成分,且具备由不同聚合度的Si-O四面体、Al-O四面体或Al-O八面体组成的岛状、链状或网状骨架结构,能够通过离子交换和专性吸附去除溶液中的重金属离子。此外,镍渣粉体表面的碱中心可以为金属阳离子提供有效的吸附位点,且表面在pH=4~12的范围内均带负电,这些都有利于金属阳离子的吸附。镍渣粉体对模拟废液中的Pb²⁺、Cu²⁺吸附实验结果显示,其对废液中的Pb²⁺、Cu²⁺均表现出较好的吸附效果,且对Pb²⁺表现出更好的选择性吸附效果。     

盐酸改性西瓜皮不溶性膳食纤维对亚硝酸盐的吸附作用

以西瓜皮为原料提取不溶性膳食纤维(IDF),并通过HCl改性,对比HCl改性西瓜皮不溶性膳食纤维(HCl-IDF)和未改性IDF对亚硝酸盐的吸附作用,探讨pH值、振荡温度、HCl-IDF添加量、吸附时间、NO-₂初始质量浓度对HCl-IDF吸附NO-₂的影响。结果表明,经HCl改性后,西瓜皮IDF对NO-₂的吸附量提升为原来的2倍;当HCl-IDF添加量为12.5g/L时,去除率为64.6%,并趋于吸附平衡;NO-₂初始质量浓度达到40mg/L时,吸附量接近饱和;升高温度、降低pH值、延长吸附时间有利于HCl-IDF对NO-₂的吸附,在pH值1.5、温度328K、吸附时间70min时可达吸附平衡;HCl-IDF对NO-₂的吸附平衡可以通过Langmuir等温方程拟合,吸附动力学行为符合Langergren准二级动力学模型,该吸附过程以化学吸附为主;HCl-IDF对NO-₂的吸附是一个吸热自发反应。     

芬顿-臭氧组合处理柠檬酸镍废水的实验研究

以初始镍质量浓度为50 mg/L的柠檬酸镍废水为研究对象,第一段采用芬顿法进行破络,第二段采用“O₃/Fe²⁺”臭氧组合工艺进一步处理。探讨了芬顿段H₂O₂投加量和臭氧组合工艺中pH、臭氧投加量、Fe²⁺投加量、干扰离子对于镍离子去除效果的影响。实验结果表明,芬顿段最佳条件:H₂O₂投加量为0.15 mL/L,初始pH为5.0,Fe²⁺投加量为111.11 mg/L,反应时间为12 min;臭氧组合工艺段最佳条件:维持O₃质量浓度为30 mg/L,反应时间为18 min,在两段工艺的最佳条件下,柠檬酸镍废水中约99.8%的柠檬酸镍得以去除,出水镍浓度达到国家排放标准。     

杂质离子对电化学矿化法固定铀的影响行为研究

本研究以金属铁为原料,采用电化学方法使金属铁逐步转化为磁性四氧化三铁,并实现同步固定铀,重点考查了杂质离子的种类、数量以及质量浓度(ρ)对废水中铀去除的影响。结果表明,离子种类和离子质量浓度的增加有助于提高电化学反应性能,加快铀的去除效率。但废水中过量的Fe³⁺和Ca²⁺在一定程度上会抑制磁铁矿的结晶,PO3－₄会与溶液中的铁离子络合形成无磁性的絮状物(Fe₃(PO₄)₂),在优化条件下反应120 min后,铀去除率最高可高达95%。     

固定床生物反应器处理铀矿冶废水中NO-3模拟试验研究

针对铀矿冶废水中存在过量硝酸根的问题,通过以轻质黏土陶粒为载体的上流式固定床生物反应器对模拟的铀矿山废水进行了NO－₃的去除试验研究。考察了载体种类、挂膜次数、NO－₃质量浓度、pH、n(C)/n(N)和水力停留时间(hydraulic retention time ,HRT)等因素对反硝化效果的影响,结果表明生物反应器对硝酸根去除效果良好。以NO－₃质量浓度为500 mg/L模拟废水进行流动实验,tHRT由6 h下降至2 h的过程中,反应体系稳定后NO－₃去除率均为100%,达到了预期的去除效果。     

生物法同时脱除高温烟气中SO2和NOx的实验研究

 对采用生物膜填料塔处理高温烟气中的SO₂和NO_x进行了实验研究,结果表明,生物膜填料塔能够有效地同时去除高温烟气中的SO₂和NO_x.在65 ℃,循环液流量4.0~7.0 L/h,pH=1.5,停留时间150 s,SO₂进气质量浓度2 000~3 000 mg/m³,NO_x进气质量浓度500~1 000 mg/m³的操作条件下,生物膜填料塔对SO₂的去除率可达99.9%以上,对NO_x的去除率为60.2%.     

NaBH4还原改性TiO2(B)及光催化性能研究

以TiCl₄为原料,在（CH₂OH）₂溶液中通过一步水热法制备单斜相二氧化钛[TiO₂(B)]。使用不同质量含量NaBH₄对TiO₂(B)进行还原改性,调控其内含Ti³⁺的浓度,合成了含Ti³⁺的TiO₂(B)-NaBH₄X样品。采用X射线衍射仪（X-ray diffraction,XRD）、拉曼光谱仪（Raman spectroscopy）、紫外-可见漫反射光谱仪（UV-visible diffuse reflectance spectroscopy,UV-DRS）、X射线光电子能谱仪(X-ray photoelectron spectroscopy,XPS）对材料进行表征。改性后TiO₂(B)-NaBH₄X样品保持其原有晶体结构,并未发生相变,仅有结晶度的改变。原始TiO₂(B)禁带宽度为3.15 eV,通过改性,Ti³⁺的存在改变了禁带宽度,成功地将禁带宽度降低到2.82 eV,将吸光区域扩展到可见光区域。通过可见光光催化分解水制氢与可见光降解甲基橙试验,确立了TiO₂(B)-NaBH₄3样品有最好的可见光光催化活性,产氢速率达到0.58 μmol·h^-1·g^-1,6 h降解率达到40%。     

四元水滑石碳纳米管在水泥净浆中对硫酸根离子的固化性能

为了提高混凝土结构抗硫酸盐侵蚀,采用共沉淀法制备钴铁镁铝四元水滑石,采用固相混合法制备钴铁镁铝水滑石-碳纳米管复合材料。将其应用于水泥净浆中,研究了龄期、浓度对固化硫酸根离子性能的影响,结果表明:和普通水泥净浆相比,加入钴铁镁铝水滑石-碳纳米管后,对SO2－₄固化能力得到了明显的提升,在7 d,SO2－₄浓度为0.05 mol/L时,其固化量由97.46 mg/g增加到107.11 mg/g;CoFeMgAl-LDHs/CNTs本身对SO2－₄固化量随着SO2－₄浓度的增加而增加,在SO2－₄浓度为0.5~1.5 mol/L时,固化量增长较为平缓,在1.5~2.5 mol/L时,固化量增长较快;固化量随着龄期的增加而增加。     

混合微波退火改性Cd2SnO4光阳极用于光电催化水氧化性能的研究

首次采用混合微波退火法制备了改性Cd₂SnO₄光阳极,有效地提高了Cd₂SnO₄光阳极的光电催化水氧化性能。采用扫描电子显微镜(scanning electron microscope, SEM)、X射线衍射仪(X-ray diffractometer, XRD)、拉曼光谱(Raman spectroscopy, Raman)、比表面积分析仪(Brunauer-Emmett-Teller surface area, BET)和稳态荧光光谱仪(photoluminescence spectroscopy, PL)等对混合微波退火改性前后的Cd₂SnO₄光阳极的表面形貌、晶体结构和组成进行了表征。性能测试结果表明,在1.70 V可逆氢电极(reversible hydrogen electrode, RHE)电压下,混合微波退火改性的Cd₂SnO₄光阳极光电流密度为12 μA/cm²,与传统热烧结制备的Cd₂SnO₄光阳极相比,其性能提升了3倍。根据电化学阻抗谱(electrochemical impedance spectra, EIS)和PL光谱测试结果可知,改性的Cd₂SnO₄光阳极的光电催化水氧化性能的提升可以归因于多孔结构导致的光生电子空穴分离速率的提升。     

Effects of La3+ and Gd3+ on Ca2+ influx in rat hepatoma H-35 cells

Effects of La³⁺ and Gd³⁺ on Ca²⁺ influx were investigated in rat hepatoma H-35 cells by measuring the initial rate of⁴⁵Ca²⁺ uptake. It was found that the maximum initial rate of Ca²⁺ uptake was increased six-to ten-fold at low concentrations of La³⁺ and Gd³⁺. Kinetic analyses by measuring the initial rate of Ca²⁺ influx at different external Ca²⁺ concentrations indicated the existence of two intracellular exchangeable components in the basal Ca²⁺ system, with low and high affinities for Ca²⁺, and only one class of Ca²⁺ binding sites was observed in the La³⁺-or Gd³⁺-treated cells. For high affinity, La³⁺ and Gd³⁺ increased both kinetic parametersK _m andV _max of basai Ca²⁺ influx. La³⁺ and Gd³⁺ compete directly with Ca²⁺ for Ca²⁺ binding site for low affinity. The kinetics is competitive.     

The40Ar/39Ar age record of formation and uplift of the blueschists and eclogites in the western Tianshan Mountains

The⁴⁰Ar/³⁹Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian (401 Ma) and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian (381 Ma). The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian (370-364 Ma). The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.     

Export of particulate organic carbon estimated from234Th-238U disequilibria and its temporal variation in the South China Sea

Activities of²³⁴Th and nutrient concentrations in the upper 500 m water column were measured at a time-series station in the South China Sea over a time span of 12.3 d. Results showed a reduction of dissolved²³⁴Th and an overall increase of particulate²³⁴Th during the period. Meanwhile, activities of total²³⁴Th kept fairly constant, implying rapid transformation of²³⁴Th between the dissolved and particulate forms. Vertical profiles of total²³⁴Th showed evident deficit of²³⁴Th relative to²³⁸U in the upper 500 m water column. Using an irreversible steady-state model of thorium scavenging, export fluxes of particulate organic carbon (POC) corresponding to time pointsT ₁ andT ₂ were estimated to be 46.5 and 13.1 mmolC · m⁻² · d⁻¹. It was demonstrated that the estimation of POC export was greatly dependent on the POC/²³⁴Th_P ratios and the bias caused by the different models of²³⁴Th scavenging, however, was considered to be of minor importance.     

含Sr2+和Bi3+有机杂化体的合成及其光降解罗丹明B

采用溶剂热法在N,N-二甲基甲酰胺溶液中合成了不同摩尔比例的SrCl_2和Bi(NO_3)_3(分别为5%,10%,30%,50%,80%)与对苯二甲酸形成的含Sr~(2+)和Bi~(3+)有机杂化体,并在紫外可见光照射下对其进行了罗丹明B降解活性的评价.结果表明:杂化体在紫外可见光下对RhB降解活性良好,其中SrCl_2摩尔比例10%掺杂的催化剂光降解活性最佳,这归结于其在紫外区域对光有很好的吸收及光生电子和空穴能有效地分离.双金属离子能协同调节有机杂化体的光催化活性.     

Potash-rich volcanic rocks and lamprophyres in western Shandong Province: 40Ar-39Ar dating and source tracing

Highly precise ⁴⁰Ar-³⁹Ar dating results demonstrate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7–124.3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (⁸⁷Sr÷⁸⁶Sr)_i ratios (0.708715–0.711418) and distinctly negative ε_nd values (−11.47–−17.54), and are enriched in radiogenic lead (²⁰⁶Pb÷²⁰⁴Pb=17.341−17.622, ²⁰⁷Pb÷²⁰⁴Pb=15.525−15.538, ²⁰⁸Pb÷²⁰⁴Pb = 37.563−37.684). Similarly, the lamprophyres also have quite low ε_nd values (−11.57–−19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings, and extensive comparisons of the Sr, Nd isotopic compositions with that of the related simultaneous rocks, it is concluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting of enriched mantle which was caused by source contamination and metasomatism of subducted continental crustal materials.     

Laser probe40Ar/39Ar dating of mica on the deformed rocks from Altyn Fault and its tectonic implications, western China

The samples of Caledonian mylonitized granite and Jurassic meta-sedimentary rocks were collected in the north of Dangjinshan Pass, Qaidam gate fault-valley and Gesi fault-valley. Detailed studies under the microscope and electronic microscope suggest that all the samples contain the syntectonic-growing minerals such as white mica, chlorite, sericite, biotite, etc. By dating these minerals, we got a group of ⁴⁰Ar/³⁹Ar laser probe isochronal ages of 89—92 Ma and apparent ages of (46.6±6.4) Ma. The ages ranging from 97 to 46 Ma were reported for the first time in the isotopic dating researches of the Altyn Fault. The isochronal age group of (98—89) Ma indicates that a ductile strike-slip event, with low-grade metamorphism, began in late Cretaceous. This suggests that the strike-slip movement of the Altyn Fault should be related to the formation of the so-called west tectonic syntaxis in the Nepal-western Kunlun area.     

Effect of fatty acids on polyamine contents and Na+/H+ antiport activity in PM vesicles isolated from roots of barley under salt stress

With 200 mmol/L NaCl treatment on barley cultivar “Jian 4” (Hordeum vulgare L. cv. J4) seedlings for 6 d, the contents of covalently and noncovalently conjugated polyamines (PAs) and activities of H⁺-ATPase in plasma membrane (PM) vesicles isolated from the roots decreased remarkably. Moreover, the activity of Na⁺/H⁺ antiport was detected first in PM vesicles. The results showed that the decrease in the contents of membrane phospholipid, noncovalently conjugated PAs and activity of H⁺-ATPase caused by NaCl could be restored partially by application of 1 mmol/L stearie acid (C_16:0) and linoleic acid (C_18:2), and C_18:2 was more effective than C_16:0 In addition, a reduction in the contents of covalently conjugated PAs was only reversed partially in the presence of C_18:2 Furthermore, Na⁺/H⁺ antiport activity was strengthened by exogenous C_16:0 and C_18:2 and C_18:2 was more effective than C_16:0. The correlative analysis suggested that, after application of C_16:0 and C_18:2 under salt stress, there was a significant positive correlation existing among phospholipid content, noncovalently conjugated PA levels, H⁺-ATPase activities and Na⁺/H⁺ antiport activities, indicating that one of the mitigative mechanisms of exogenous fatty acids on salt injury was to improve membrane phospholipid and PA contents, leading to an enhance in membrane integrity and a change in charge status of PM vesicles, so the activity of membrane-associated enzyme H⁺-ATPase was increased and synthesis of Na⁺/H⁺ antiport protein was activated.     

黑鲷NKCC1分子特征及其对急性盐度胁迫的表达响应

为了解黑鲷(Acanthopagrus schlegelii)在盐度胁迫过程中的适应机制,本研究利用基因扩增、聚类分析、荧光定量PCR等技术对NKCC1基因进行生物信息学分析以及在不同组织中的表达特征研究,并探讨其在急性盐度胁迫下的表达机制。结果表明NKCC1基因的开放阅读框(Open Reading Frame, ORF)为3 504 bp,共编码1 167个氨基酸,预测蛋白分子量为127.19 kDa,理论等电点为5.75。结构域分析表明黑鲷NKCC1分子为跨膜蛋白,并包含一个典型的Na~+-K~+-Cl~-共同转运蛋白SLC12A结构域,且在不同物种中具有很高的保守性;序列比对分析表明黑鲷NKCC1氨基酸序列与金头鲷NKCC1a的同源性最高,为97.8%;组织表达分析表明黑鲷NKCC1基因在所检测的12个组织,即肝脏、肾脏、心、脑、眼、鳃、鳍条、脾脏、皮肤、肠、性腺和白肌中均有表达,其中在肾脏、鳃和肠中表达量最高,并显著高于其他组织(P0.05);在低盐度胁迫下,NKCC1基因在鳃组织中的表达量对盐度变化响应十分迅速,而在肾脏组织中,低盐度和高盐度胁迫都会在不同时间点抑制NKCC1基因的表达量。综上所述,本研究为解析NKCC1基因在黑鲷调节渗透压和离子平衡过程中的功能机制奠定了基础,并为促进黑鲷养殖产业的可持续发展提供一定的技术理论。     

Export and remineralization of POM in the Southern Ocean and the South China Sea estimated from 210Po/210Pb disequilibria

Disequilibria between ^210Po and ^210Pb in the upper water and their potential applications as a proxy of particle export and remineralization were examined in the Southern Ocean （station IV3） and the South China Sea （NS44）. ^210po was deficit in surface waters but excessive relative to ^210Pb in subsurface waters. Good positive correlation between ^210Po and particulate organic carbon （POC） indicated deficits and excess of ^210Po resulted from particulate organic matter （POM） export and remJneralization respectively, which was also supported by the decreased δ^13C and increased δ^15N downwards as a result of particle remineralization. On the basis of ^210Po/^210Pb box-model, POC export flux out of the surface waters were 1.2 mmol C. m^-2. d^-1 and 2.3 mmol C. m^-2. d^-1 for station NS44 and IV3, respectively. In the subsurface waters, remineralization fluxes of ^210Po were 0.062 Bq. m^-2.d^-1 and 0.566 Bq.m^-2.d^-1 for station NS44 and IV3 along with the recycle efficiency of 52±26% and 119±52%, respectively. Remineralized fluxes of POM derived from ^210Po and exported POC were 0.6 mmol C.m^-2.d^-1 and 2.7 mmol C. m^-2. d^-1 for NS44 and IV3. This study suggested that ^210Po was a powerful tracer of particle export and remineralization.