Chlorinating Mechanism of Cerium Dioxide by NH_4Cl

The chlorinating mechanism of cerium dioxide was investigated by chlorinating CeO 2 with NH 4Cl and thermal analysis, which is useful for chlorinating RE minerals such as bastnasite by NH 4 Cl and preparing anhydrous RE chloride. The results indicate that NH 4Cl directly takes part in the chlorination of cerium dioxide by forming an intermediate CeOCl rather than by the HCl decomposed from NH 4Cl. Based on the chlorinating ratio of cerium dioxide being about 80% at 300 ℃ and decreasing at higher temperature, it is must be owing to thermal decomposition of CeCl 3·7H 2O. The thermal analysis experiments further prove the existence of CeOCl in the decomposition of CeCl 3·7H 2O, which loses 4H 2O, 5H 2O, 6H 2O and 7H 2O, stepwise and finally CeCl 3 is decomposed to CeOCl. Therefore chlorinating cerium dioxide with NH 4Cl should strictly control the temperature and time, and over dose NH 4Cl should be also applied as well.

Unveiling the geometric site dependent activity of spinel Co_(3)O_(4)for electrocatalytic chlorine evolution reaction

Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost CER.Herein,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied potentials.Guided by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity significantly.Our work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level.

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late stroke.Indeed,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain tissue.Our previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently unclear.To simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic stroke.We found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous acid.Further,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid hydrazide.Our results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/reoxygenation.However,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and astrocytes.This suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion injury.Lower levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-catenin.By transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear translocation.Altogether,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

Molecular packing tuning via chlorinated end group enables efficient binary organic solar cells over 18.5%

Designing novel nonfullerene acceptors(NFAs)is of vital importance for the development of organic solar cells(OSC).Modification on the side chain and end group are two powerful tools to construct efficient NFAs.Here,based on the high-performance L8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining the backbone of BON3.Then we introduced different halogen atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1Hinden-1-ylidene)malononitrile end group(EG)to construct efficient NFAs named BON3-F and BON3-Cl,respectively.Polymer donor D18 was chosen to combine with two novel NFAs to construct OSC devices.Impressively,D18:BON3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a high open-circuit voltage(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the highest binary PCE of devices based on D18 as the donor.However,BON3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,higher electron and hole mobilities,reduced charge recombination,and enhanced molecular packing in the D18:BON3-Cl films.Also,we performed stability tests on two binary systems;the D18:BON3-Cl and D18:BON3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storage at 85°C in an N2-filled glove box,respectively.Our work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BON3-Cl for further improvement of PCE.

Effects of surface chlorine atoms on charge distribution and reaction barriers for photocatalytic CO_(2)reduction

Photocatalytic CO_(2)reduction to produce high value-added carbon-based fuel has been proposed as a promising approach to mitigate global warming issues.However,the conversion efficiency and product selectivity are still low due to the sluggish dynamics of transfer processes involved in proton-assisted multi-electron reactions.Lowering the formation energy barriers of intermediate products is an effective method to enhance the selectivity and productivity of final products.In this study,we aim to regulate the surface electronic structure of Bi_(2)WO_(6)by doping surface chlorine atoms to achieve effective photocatalytic CO_(2)reduction.Surface Cl atoms can enhance the absorption ability of light,affect its energy band structure and promote charge separation.Combined with DFT calculations,it is revealed that surface Cl atoms can not only change the surface charge distribution which affects the competitive adsorption of H_(2)O and CO_(2),but also lower the formation energy barrier of intermediate products to generate more intermediate*COOH,thus facilitating CO production.Overall,this study demonstrates a promising surface halogenation strategy to enhance the photocatalytic CO_(2)reduction activity of a layered structure Bi-based catalyst.

The Toxic Effects of Strong Chlorin Disinfectant on Mangroves and Emission Thresholds

In this study, based on the simulated discharge results of chemical disinfectants, hypocotyl germination concentration gradient pre-test and concentration gradient determination experiment were set up respectively. Laboratory cultivation was conducted to compare and analyze the root germination and germination indexes, three mangrove hypocotyls of Kandelia candel (Linn.) Druce, Ceriopstagal C.B. Rob. and Bruguiera sexangula var. Rhynchopetalas’ efficiency of cumulative root germination, cumulative germination and the cumulative expansion of the second pair of leaves, one-way analysis of variance was used to obtain the tolerance threshold of three mangrove hypocotyls to strong chlorin disinfectant. The study determined that the by-products of strong chlorin disinfectant, the toxic threshold concentrations of Kandelia candel (Linn.) Druce, Ceriopstagal C.B. Rob. and Bruguiera sexangula var. rhynchopetala are close to 0.55 mg/L, 0.55 mg/L and 0.25 mg/L, respectively. This concentration range is lower than the average concentration of 1.183 mg/L of active chlorine emitted from strong chlorine concentrate during pond clearing in high-level shrimp ponds, indicating that transient emissions of strong chlorine concentrate during pond clearing can have a toxic effect on mangrove plants. The strength of tolerance of the embryonic axes of the three mangrove species to effective chlorine contamination was, Ceriopstagal C.B. Rob. stronger than Bruguiera sexangula var. rhynchopetala, and Kandelia candel (Linn.) Druce is the weakest.

Effects of Chlorine and Chlorine Monoxide on Stratospheric Ozone Depletion

This paper presents a system approach of mass balance calculations of ozone and other species under diffusion-convection-reaction processes to study the impacts of major ozone-depleting chemicals, chlorine (Cl) and chlorine monoxide (ClO), and the effect of photolysis on ozone concentrations, ozone depletion, total ozone abundance, and ozone layer along the altitude in the stratosphere. The calculated ozone concentrations and profile of the layer followed a similar trend and were generally in good agreement with the measurements above the tropical area. The calculated peak of the layer was at the same mid-stratosphere at Z = 30 km with a peak concentration and total ozone abundance about 20% higher than the measured peak concentration of 8.0 ppm and total abundance of 399 DU. In the presence of Cl and ClO, the calculated ozone concentrations and total abundance were substantially reduced. Cl generally depleted more uniformly of ozone across the altitude, while ClO reduced substantially the ozone in the upper stratosphere and thus shifted the peak of the layer to a much lower elevation at Z = 14 km. Although both ClO and Cl are active ozone-depleting chemicals, ClO was found to have a more pronounced impact on ozone depletion and distribution than Cl. The possible explanations of these interesting phenomena were discussed and elaborated. The approach and calculations in this paper were shown to be useful in providing an initial insight into the structure and behavior of the complex ozone layer.

Lithium extraction from hard rock lithium ores(spodumene,lepidolite,zinnwaldite,petalite):Technology,resources,environment and cost

Lithium production in China mainly depends on hard rock lithium ores,which has a defect in resources,environment,and economy compared with extracting lithium from brine.This paper focuses on the research progress of extracting lithium from spodumene,lepidolite,petalite,and zinnwaldite by acid,alkali,salt roasting,and chlorination methods,and analyzes the resource intensity,environmental impact,and production cost of industrial lithium extraction from spodumene and lepidolite.It is found that the sulfuric acid method has a high lithium recovery rate,but with a complicated process and high energy consumption;alkali and chlorination methods can directly react with lithium ores,reducing energy consumption,but need to optimize reaction conditions and safety of equipment and operation;the salt roasting method has large material flux and high energy consumption,so require adjustment of sulfate ratio to increase the lithium yield and reduce production cost.Compared with extracting lithium from brine,extracting lithium from ores,calcination,roasting,purity,and other processes consume more resources and energy;and its environmental impact mainly comes from the pollutants discharged by fossil energy,9.3-60.4 times that of lithium extracted from brine.The processing cost of lithium extraction from lepidolite by sulfate roasting method is higher than that from spodumene by sulfuric acid due to the consumption of high-value sulfate.However,the production costs of both are mainly affected by the price of lithium ores,which is less competitive than that of extracting lithium from brine.Thus,the process of extracting lithium from ores should develop appropriate technology,shorten the process flow,save resources and energy,and increase the recovery rate of related elements to reduce environmental impact and improve the added value of by-products and the economy of the process.

A new perspective to develop regiorandom polymer acceptors with high active layer ductility,excellent device stability,and high efficiency approaching 17%

The recently reported efficient polymerized small-molecule acceptors(PSMAs)usually adopt a regioregular backbone by polymerizing small-molecule acceptors precursors with a low-reactivity 5-brominated 3-(dicyanomethylidene)indan-1-one(IC)end group or its derivatives,leading to low molecular weight,and thus reduce active layer mechanical properties.Herein,a series of newly designed chlorinated PSMAs originating from isomeric IC end groups are developed by adjusting chlorinated positions and copolymerized sites on end groups to achieve high molecular weight,favorable intermolecular interaction,and improved physicochemical properties.Compared with regioregular PY2Se-Cl-o and PY2Se-Cl-m,regiorandom PY2Se-Cl-ran has a similar absorption profile,moderate lowest unoccupied molecular orbital level,and favorable intermolecular packing and crystallization properties.Moreover,the binary PM6:PY2Se-Cl-ran blend achieves better ductility with a crack-onset strain of 17.5% and improved power conversion efficiency(PCE)of 16.23% in all-polymer solar cells(all-PSCs)due to the higher molecular weight of PY2Se-Cl-ran and optimized blend morphology,while the ternary PM6:J71:PY2Se-Cl-ran blend offers an impressive PCE approaching 17% and excellent device stability,which are all crucial for potential practical applications of all-PSCs in wearable electronics.To date,the efficiency of 16.86% is the highest value reported for the regiorandom PSMAs-based all-PSCs and is also one of the best values reported for the all-PSCs.Our work provides a new perspective to develop efficient all-PSCs,with all high active layer ductility,impressive PCE,and excellent device stability,towards practical applications.

Study of engineering electronic structure modulated non-noble metal oxides for scaled-up alkaline blend seawater splitting

Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a significant impact on hydrogen commercialization.Herein,we prepared energy-efficient,scalable,and engineering electronic structure modulated Mn-Ni bimetal oxides(Mn_(0.25)Ni_(0.75)O)through simple hydrothermal followed by calcination method.As-optimized Mn_(0.25)Ni_(0.75)O displayed enhanced oxygen and hydrogen evolution reaction(OER and HER)performance with overpotentials of 266 and115 mV at current densities of 10 mA cm^(-2)in alkaline KOH added seawater electrolyte solution.Additionally,Mn-Ni oxide catalytic benefits were attributed to the calculated electronic configurations and Gibbs free energy for OER,and HER values were estimated using first principles calculations.In real-time practical application,we mimicked industrial operating conditions with modified seawater electrolysis using Mn_(0.25)Ni_(0.75)O‖Mn_(0.25)Ni_(0.75)O under various temperature conditions,which performs superior to the commercial IrO_(2)‖Pt-C couple.These findings demonstrate an inexpensive and facile technique for feasible large-scale hydrogen production.

Current status and prospects of research on 1,4-dioxane pollution and treatment technologies in the water environment

1,4-dioxane pollution is characterized by its early identification, widespread sources and extensive distribution. The pollutant is highly mobile and persistent in the water environment and is classified as a B2(probable) human carcinogen. After reviewing recent researches on the pollution status,transport and transformation characteristics of 1,4-dioxane in the water environment, as well as the environmental pollution remediation and treatment technologies, and the status of environmental regulation,this paper addresses that the distribution of 1,4-dioxane in water bodies is significantly correlated with chlorinated hydrocarbon pollutants such as 1,1,1-trichloroethane(1,1,1-TCA) and trichloroethylene(TCE).It is noteworthy that 1,4-dioxane often occurs in symbiosis with 1,1,1-TCA and has a similarity contamination plume distribution to 1,1,1-TCA. The natural attenuation of 1,4-dioxane in groundwater environment is weak, but there is a certain degree of biological oxidation attenuation. Current methods for treating 1,4-dioxane pollution mainly include extraction-treatment technology, advanced oxidation treatment technology, modified biological treatment technology and phytoremediation technology, all of which have their limitations in practical application. Currently, there is no environmental regulation available for the 1,4-dioxane pollution worldwide, and no enforceable standard established for defining the health trigger levels of 1,4-dioxane in drinking water. Research on this contaminant in China is generally limited to the site or laboratory scale, and there are no studies on the environmental risk and quality standards for 1,4-dioxane in the water environment.

高冰镍氯气浸出基础研究──浸出过程热力学

高冰镍氯气浸出基础研究──浸出过程热力学杨显万，李敦钫，何蔼平，刘中华（昆明工学院，昆明６５００９３）１前言高冰镍氯气浸出过程的热力学，国内外有人作过一些工作。早在七十年代就有人利用Ｎｉ２＋活度系数在氯盐水溶液中随溶液离子强度的升高而显著上升的特性，...

Modified calcination conditions of rare alkali metal Rb-containing muscovite(KAl_2[AlSi_3O_(10)](OH)_2)

Muscovite mineral was roasted in different conditions.Rubidium leaching rate was a standard to examine the impact of various factors on calcination effect,including the agent types,roasting time,mass ratio,and roasting temperature.The results indicate that the best agent is the combination of sodium chloride and calcium chloride,and its mass ratio of muscovite/NaCl/CaCl2is1.00:0.25:0.25.Calcined at 850℃ for 30 min,the rubidium leaching rate is up to 90.12%.The reaction of muscovite ore with the chlorinating agent CaCl2was studied by TG/DSC,and the surface morphology before and after leaching was characterized by SEM.Rubidium chloride products can be obtained using t-BAMBP extraction,hydrochloric acid re-extraction,and purification.

藻胆体耦合Chlorin e_6染料敏化太阳能电池的研究

采用超声波破碎结合蔗糖密度梯度离心的方法从钝顶螺旋藻中分离出纯度较高的完整藻胆体,探讨了具有超大分子结构的藻胆体作为染料敏化太阳能电池(DSSC)敏化剂的可行性,考察了藻胆体与Chlorin e6在纳米Ti O2电极上的耦合敏化作用。研究发现,藻胆体可以组装在纳米Ti O2电极上作为DSSC的敏化剂,藻胆体DSSC的开路电压0.55 V,短路电流0.50 mA/cm2,光电转化效率0.19%;藻胆体与Chlorin e6耦合敏化可以增大DSSC的短路电流,提高光电转化效率,且高于藻胆体和Chlorin e6单独敏化的加和,表现出明显的耦合效应,为进一步探讨光合膜蛋白在光电材料中的应用奠定了基础。

Chlorin e6在S180肉瘤荷瘤小鼠体内的分布

目的研究Chlorin e6在肿瘤组织的富集情况,探索给药后最佳的超声辐射时间。方法 S180肉瘤荷瘤小鼠腹腔注射Chlorin e6后,利用共聚焦显微镜观测其在肿瘤和周围肌肉组织的富集变化及代谢。结果腹腔给药18h后,Chlorin e6在肿瘤和周围肌肉组织含量均达最高峰,且差异最明显,此时为最佳的超声辐射时间。结论 Chlorin e6具有肿瘤靶向性好、正常组织清除快的优点。Chlorin e6声动力疗法的时间点应选择在18h左右。

二氢卟吩e6光动力学疗法对人舌鳞癌细胞株Tca8113的杀伤作用

目的:探讨二氢卟吩e6(Ce6)光动力学疗法(Ce6-PDT)对体外培养人舌鳞癌Tca8113细胞的杀伤作用。方法:向体外培养的人舌鳞癌Tca8113细胞中加入Ce6,浓度分别为5、10、20、50和100μg/ml,孵育1.5h,予波长630 nm半导体激光照射,照射的功率密度为100mW/cm2,能量密度分别为0.5、1、2、5、10和15J/cm2,继续孵育6h,用MTS比色法测定细胞存活率。结果:(1)不受光照的条件下,较低浓度Ce6(<10μg/ml)与细胞共同培养而对细胞的毒性较小,Ce6浓度为20μg/ml时对细胞的杀伤率约为10%。(2)光照条件下,Ce6-PDT能有效地杀伤体外培养的人舌鳞癌Tca8113细胞,其杀伤作用与Ce6浓度及光照剂量正相关,呈浓度/剂量依赖性(P<0.01)。结论:Ce62PDT能有效地杀伤体外培养的人舌鳞癌Tca8113细胞;Ce6在较大浓度下对细胞有毒性。

Damping Properties of Piezoelectric and Electrical Conductive of BaTiO_3/VGCF/CPE Composites: Effect of Carbon Fiber

A new damping composite of CPE/BaTiO3/VGCF has been developed on the basis of the piezo- effect and conductivity mechanism. The conductivity of composites varied with the VGCF content are tested and analyzed.The results indicate that the conductivity of composites grows up slowly as the VGCF content is in the range of 10%-20%. It is very useful for industrial application to control the conductivity of composites by adjusting the VGCF content. In addition, at the range of - 50 - 120°C,the dependence of loss factor on the VGCF content varied with the temperature are tested and analyzed by dynamic mechanical and dielectric behavior measurement of the composites, and expected results are obtained.

e4声动力治疗小鼠S180肉瘤的实验研究

目的本文研究超声激活声敏剂e4对在体小鼠S180肉瘤的杀伤作用。方法荷瘤小鼠腹腔注射e4(40mg/kg),6小时后用频率为1.0MHz超声波照射肿瘤区域180s,超声强度分3组:0.4W/cm2,0.8W/cm2,1.6W/cm2。以空白对照组,单纯超声组(超声强度为1.6W/cm2),单纯声敏剂组为对照组,每两天测量肿瘤大小,12天后剥离肉瘤并称重比较。结果e4在小鼠体内经超声激活后可明显抑制肿瘤生长。在超声强度为0.4W/cm2～0.8W/cm2范围时,e4对肿瘤的抑制作用随声强的增加疗效亦增加。结论e4声动力治疗对小鼠S180肉瘤有明显杀伤或抑制作用,在一定范围内其作用大小与超声强度正相关。声动力疗法有望成为临床治疗肿瘤的新方法。

光敏剂e4光动力学治疗小鼠S-180肉瘤的实验研究

目的:利用激光激活e4,研究对在体小鼠S180肉瘤的杀伤作用,证明e4是可以选用的新型光敏剂之一。方法:荷瘤小鼠腹腔注射e4(40mg/kg)1次,6小时后用强度为24W/cm2的激光照射肿瘤区域1次,时间为20分钟(PDT组)。以空白对照组(C),光照组(Light)(激光强度为20W/cm2),光敏剂组(e4)为对照组,每两天测量肿瘤的大小,12天后剥离肉瘤并称重比较。结果:e4在小鼠体内经激光激活后可明显抑制肿瘤生长,PDT组肿瘤的平均重量较空白对照组肿瘤的平均重量要轻,两者比较有统计学意义,P=0.0000,光敏剂组肿瘤的平均重量较空白对照组肿瘤的平均重量要轻,两者比较有统计学意义,P=0.0068。结论:e4光动力治疗对小鼠S-180肉瘤有明显杀伤或抑制作用,e4自身对小鼠S-180肉瘤有一定杀伤或抑制作用。

浅议某静电植绒厂废水处理

本文通过小试与工程实践指出:对某静电植绒厂含酸性染料废水处理采用混凝与活性炭吸附工艺的物化处理方法是可行的。这种方法尤其适合于小型印染厂;如有必要时还可解决废水的回用问题。