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Thorium anomaly on the lunar surface and its indicative meaning

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Acta Geochimica 2024年第3期43卷 507-519页

作者： Jingyi ZHANG Jianzhong Liu Center for Lunar and Planetary Science Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Moon has been divided into three terranes:Procellarum KREEP Terrane(PKT),Feldspathic Highland Terrane(FHT),and South Pole-Aitken Terrane(SPAT),using globally measured Th and FeO.Many lunar evolu-tion models have predicted that a lunar magma ocean will produce a residual layer enriched in incompatible elements such as K,REE,and P(i.e.,KREEP)in the late age of crys-tallization;and that the distribution of thorium can be used as a proxy for determining the global distribution of KREEP.The thorium distribution in these three terranes is inhomo-geneous.The highest concentration of thorium is in PKT,the medium concentration of thorium is in SPAT,and almost none in FHT.Then what is the specific distribution in each of the terrane and what enlightenment can it tell us?Here we present and describe the detailed thorium distribution in PKT,SPAT,and FHT and provide some information for the origin of asymmetries on the lunar surface.

关键词： Procellarum KREEP Terrane(PKT) Feldspathic Highland Terrane(FHT) South Pole-Aitken Terrane(SPAT) KREEP Thorium abundance

Observed Vertical Structure of Precipitation over the Southeastern Tibetan Plateau in Summer 2021

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Journal of Meteorological Research 2023年第1期37卷 90-106页

作者： Gaili WANG Renran ZHOU Jingyi ZHANG Ran LI State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

Mêdog County,with its mountains and valleys,is located in the southeastern Tibetan Plateau(TP)and at the lower reaches of the Yarlung Zangbo River.This area has the highest annual rainfall amount over the TP,and in situ measurements are very scarce due to frequent debris flows and transportation difficulties.A monitoring campaign focused on cloud and precipitation observations was established in Mêdog in 2019 as a part of the Second Tibetan Plateau Scientific Expedition and Research Program.This paper evaluates the accuracy of micro rain radar(MRR)measurements and investigates the variations in precipitation vertical structure in Mêdog using observations collected from the MRR,disdrometer,and rain gauges in summer 2021.The measurements from the three instruments show a strong consistency,with correlation coefficients exceeding 0.93.Although the profiles of integral rain parameters for different rain rate categories in Mêdog are similar to those in other regions,the vertical evolution of raindrop size distributions shows significant differences.For lightest rain,the evaporation of small raindrops and breakup of large raindrops are clear during their descent.For the rainfall rate category of 0.2–2.0 mm h−1(2.0–20.0 mm h−1),concentrations of small and medium(large)drops show almost uniform vertical structures,while the large(medium)drop number displays a positive(negative)gradient.A disturbance at height of 1.5–2.0 km above ground level(AGL)is observed in the heavy rainfall due to strong updrafts.In general,the MRR measurements in Mêdog are robust.The raindrop breakup process is more apparent in Mêdog than in other regions,resulting in high concentration of sizelimited raindrops.In addition,it is found that the interaction between steep terrain and Mêdog convective rain causes the strong updrafts between 1.5 and 2.0 km AGL.

关键词： precipitation vertical structure Tibetan Plateau raindrop size distribution(DSD) micro rain radar strong updraft

Oxidative degradation of phenol by sulfidated zero valent iron under aerobic conditions:The effect of oxalate and tripolyphosphate ligands

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Journal of Environmental Sciences 2021年第2期33卷 82-89页

作者： Xianglong Kong Chengwu zhang Jingyi ZHANG Lishuang Xuan Chuanyu Qin Key Laboratory of Groundw ater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Prouindal Key Laboratory of Water Resources and Enuironment jinin UniversityChangchun 130021China National and Local Joint Engineering Laboratory for Petrochem ical Contaminated Site Control and Remediation Technology Jilin UniversityChangchun 130021China

After adding either organic or inorganic ligands,sulfidated nano-zero-valent iron(Sn ZVI)was used for aerobic degradation of phenol,and the effect of the ligand species on oxidation performance was investigated.We found that Sn ZVI hardly degraded phenol in the absence of ligand addition.Ligands initiated and promoted the degradation of pollutants by Sn ZVI.The data herein show that a characteristic inorganic ligand,tripolyphosphate(TPP),is more effective in enhancing oxidation than a characteristic organic ligand oxalate.In addition to the scavenging of reactive oxidants by the organic ligand,more ferrous ion(Fe(Ⅱ))dissolution from Sn ZVI in the TPP system is another cause for the superior enhancement by the inorganic ligand.In the oxalate system,as the sulfur content of Sn ZVI increased,the oxidation efficiency increased because Fe S shell promoted the transfer of electrons to produce more reactive oxygen species(ROS).In TPP system,the effect of sulfur content on oxidation performance is more complex.The Sn ZVI with low sulfur content showed poor oxidation performance compared with that of n ZVI.Further experiments proved that sulfidation might weaken the complexation of TPP with surface bound Fe,which would slow down the ionic Fe(II)dissolution rate.Therefore,sulfidation has the dual effects of enhancing electron transfer and inhibiting the complexation of inorganic ligands.In addition,the mechanisms of ROS generation in different ligand systems were investigated herein.Results showed that the critical ROS in both the oxalate and TPP systems are hydroxyl radicals,and that they are produced via one-electron activation of O_(2).

关键词： Zero valent iron Sulfidation Tripolyphosphate Oxalate Oxygen activation

Metal-free intramolecular hydroarylation of alkynes

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Organic Chemistry Frontiers 2022年第5期9卷 1300-1307页

作者： Chaofeng zhang Songkui Lv Yanru Wang Jingyi ZHANG Xiao-Na Wang Junbiao Chang Collaborative Innovation Center of New Drug Research and Safety Evaluation Henan ProvinceKey Laboratory of Advanced Drug Preparation TechnologiesMinistry of EducationSchool of Pharmaceutical SciencesZhengzhou UniversityZhengzhou 450001P.R.China

An efficient metal-free intramolecular hydroarylation reaction of alkynes is described here.A series of aryl and N-group attached alkynes generated the intramolecular hydroarylation products in high yields.

关键词： intramolecular alkynes free

Conduction-convection coupled heat transfer around a hollow cylinder under different buoyancy forces

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Chinese Journal of Aeronautics 2024年第4期37卷 216-228页

作者： Wanyu zhang jingyi WU Guang YANG Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China

In order to clarify the effect of a buoyancy force on conduction–convection coupled heat transfer in a hollow cylinder, the flow and thermal characteristics were analyzed using an RNG k-ε turbulence model. The Reynolds number was fixed at 1.014 × 10^(6), and the Rayleigh number varied from 1.122 × 10^(10)to 1.088 × 10^(11). Results have shown that, when considering the effect of an opposed buoyancy force, increasing the Rayleigh number has a positive impact on the rate of change and uniformity of the cylinder temperature. The temperature distributions along the axial and circumferential directions are similar for different Rayleigh numbers, but extreme values differ.Along the axial direction, the maximum temperature is obtained at the interface between the variable-diameter part and the constant-diameter part. The maximum dimensionless temperature value decreases to 0.12 when the Rayleigh number increases to 1.088 × 10^(11). Along the circumferential direction, the temperature distribution is affected by the buoyancy force, which results in the temperature of the upper part being higher than that of the lower part. After nondimensionalization of the temperature and time, a correlation was proposed to illustrate the transient heat transfer process quantitatively. The standard deviation of the maximum relative temperature, representing the temperature uniformity, was also calculated. It was found that the difference in the direction of the buoyancy force made a huge difference. Compared with the opposed buoyancy force, the maximum dimensionless temperature is almost two times higher with an assisted buoyancy force. Similarly, the heat transfer coefficient with an assisted buoyancy force is half of that with an opposed buoyancy force. Overall, an assisted buoyancy force plays a negative role in terms of thermal characteristics. The flow field around the hollow cylinder was also illustrated to reveal the mechanism of the buoyancy force on magnitude and direction aspects.

关键词： Buoyancy Conduction-convection heat transfer Transient analysis Hollow cylinder Non-dimensionalization

Effects of ultrasonication on the DBP formation and toxicity during chlorination of saline wastewater effluents

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Journal of Environmental Sciences 2022年第7期34卷 326-335页

作者： Yu Li Wanxin Li Xiangru zhang jingyi Jiang School of Environment Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong KongChina

Chlorine disinfection of saline wastewater effluents rich in bromide and iodide forms relatively toxic brominated and iodinated disinfection byproducts(DBPs). Ultrasonication is a relatively new water treatment technology, and it is less sensitive to suspended solids in wastewaters. In this study, we examined the effects of ultrasonication(in terms of reactor type and combination mode with chlorination) on the DBP formation and toxicity in chlorinated primary and secondary saline wastewater effluents. Compared with the chlorinated wastewater effluent samples without ultrasonication, ultrasonic horn pretreatment of the wastewater effluent samples reduced the total organic halogen(TOX) levels in chlorination by ~30%, but ultrasonic bath pretreatment of the wastewater samples did not significantly change the TOX levels in chlorination, which might be attributed to the higher energy utilization and decomposition extent of organic DBP precursors in the ultrasonic horn reactor. Moreover, the TOX levels in the chlorinated samples with ultrasonic horn pretreatment(USH–chlorination), simultaneous treatment(chlorination + USH) and subsequent treatment(chlorination–USH) were also significantly reduced, with the maximum TOX reductions occurring in the samples with ultrasonic horn pretreatment. A toxicity index was calculated by weighting and summing the levels of total organic chlorine, total organic bromine and total organic iodine in each treated sample. The calculated toxicity index values of the chlorinated wastewater effluent samples followed a descending rank order of “chlorination” > “chlorination + USH” > “chlorination–USH” > “USH–chlorination”, with the lowest toxicity occurring in the samples with ultrasonic horn pretreatment. Then, a developmental toxicity bioassay was conducted for each treated sample. The measured toxicity index values of the chlorinated wastewater samples followed the same descending rank order.

关键词： Disinfection byproducts DBPs Chlorination Ultrasonication Developmental toxicity

Degradation of organic contaminants through the activation of oxygen using zero valent copper coupled with sodium tripolyphosphate under neutral conditions

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Journal of Environmental Sciences 2020年第4期32卷 375-384页

作者： Chengwu zhang Lishuang Xuan Jingyi ZHANG Fang Yuan Xianglong Kong Chuanyu Qin Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Water Resources and Environment Jilin UniversityChangchun 130021China National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology Jilin UniversityChangchun 130021China

In this study,sodium tripolyphosphate(STPP)was used to promote the removal of organic pollutants in a zero-valent copper(ZVC)/O2 system under neutral conditions for the first time.20 mg/L p-nitrophenol(PNP)can be completely decomposed within 120 min in the ZVC/O2/STPP system.The PNP degradation process followed pseudo-first-order kinetics and the degradation rate of PNP gradually increased upon the decreasing ZVC particle size.The optimal pH of the reaction system was 5.0.Our mechanism investigation showed that Cu+generated by ZVC corrosion was the main reducing agent for the activation of 02 to produce ROS.-OH was identified as the only ROS formed during the degradation of PNP and its production pathway was the double-electron activation of O2(O2→H2 O2→·OH).In this process,STPP did not only promote the release of Cu+through its complexation,but also promoted the production of OH by reducing the redox potential of Cu2+/Cu+.In addition,we could initiate and terminate the reaction by controlling the pH.At pH8.1,the reaction was terminated.STPP was recycled to continuously promote the corrosion of ZVC and O2 activation as long as the pH was<8.1.This study provided a new and efficient way for O2 activation and organic contaminants removal.

关键词： Sodium tripolyphosphate Zero valent copper corrosion Oxygen activation pH control

Experimental study on the controlling factors of frictional coefficient for lost circulation control and formation damage prevention in deep fractured tight reservoir

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Petroleum 2022年第3期8卷 352-362页

作者： Chengyuan Xu Honglin zhang Mingming Zhu Yili Kang Xiaopeng Yan Jingyi ZHANG Yingrui Bai State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduChina School of Petroleum Engineering China University of Petroleum(East China)QingdaoChina Changqing Drilling Branch CNPC Chuanqing Drilling Engineering Co.Ltd.Xi'an 710000China

Working fluids loss is a major contributor to low productivity during production process of fractured tight reservoirs.Lost circulation control effect directly related to the tribological behavior between fracture surface and lost circulation materials(LCMs).In this study,the friction coefficient(FC)was investigated using typical clastic rocks and LCMs by considering multiple effect factors divided into external condition and internal condition.The results show that normal load had a relatively high effect on sliding model.A positive correlation was observed between FC and asperities heights.FC decreased induced by particle size degradation of rigid LCMs.Elastic LCMs manifested higher FC compared with rigid LCMs.Under the lubrication condition by working fluid,FC of rigid LCMs was mainly controlled by their surface wettability.FC of organic LCMs is more sensitive to high temperature aging than inorganic LCMs.Fracture plugging experiments show that LCMs optimized based on the research results can effectively improve the efficiency and strength of fracture plugging.

关键词： Fractured tight reservoirs Lost circulation control Friction coefficient Lost circulation materials

Particle size spatial distribution in landslide dams

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Journal of Mountain Science 2024年第6期21卷 1886-1903页

作者： zhang jingyi zhang Jianmin State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610064China

The particle composition and spatial distribution of landslide-induced dam bodies are critical geotechnical parameters for studying the hazards of dam-break floods.However,current research often neglects the influence of the initial particle composition and spatial distribution of the landslide on the particle composition and spatial distribution of the landslide dam.This study investigated the impact of initial particle size distribution,volume,and sliding length on the energy and velocity changes of characteristic particles during the sliding process and the spatial distribution of particle sizes in the landslide dam body.Numerical simulations and physical models were employed to examine the effects of sequential gradient arrangements(where particle sizes decrease from top to bottom)and four other different initial particle arrangements on the energy and velocity changes of particles and the spatial distribution of particle sizes in the dam body.The study reveals the characteristics of translational and rotational energy of different particles and the laws of mechanical energy conversion,obtaining the spatial distribution patterns of particle sizes in landslide-induced dams.The results show that under the sequential gradient arrangement,the energy dissipation of the landslide movement is lower,with larger particles mainly distributed at the distal end and smaller particles at the proximal end of the landslide dam.In contrast,under the reverse gradient arrangement,the energy dissipation of the landslide movement is higher,and the distribution pattern of the dam particles is opposite to that of the sequential gradient arrangement.For the other arrangement modes,the spatial distribution of dam particles falls between the aforementioned two.There is a positive correlation between particle size and translational kinetic energy within the particle flow during the landslide process,and rotational motion increases energy dissipation.Under constant slope conditions,sliding length does not affect the movement pattern of

关键词： Particle size distribution Landslide Numerical simulation Discrete element method