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Geochemistry of Rare earth Elements(REE) in the Weathered Crusts from the Granitic Rocks in Sulawesi Island, Indonesia

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Journal of earth Science 2014年第3期25卷 460-472页

作者： Adi Maulana Kotaro Yonezu Koichiro Watanabe department of Geology engineering Faculty of Engineering Hasanuddin University department of earth resources engineering Kyushu University

We report for the first time the geochemistry of rare earth elements（REE） in the weathered crusts of I-type and calc-alkaline to high-K（shoshonitic） granitic rocks at Mamasa and Palu region, Sulawesi Island, Indonesia. The weathered crusts can be divided into horizon A（lateritic profile） and B（weathered horizon）. Quartz, albite, kaolinite, halloysite and montmorrilonite prevail in the weathered crust. Both weathered profiles show that the total REE increased from the parent rocks to the horizon B but significantly decrease toward the upper part（horizon A）. LREE are enriched toward the upper part of the profile as shown by La/YbN value. However, HREE concentrations are high in horizon B1 in Palu profile. The total REE content of the weathered crust are relatively elevated compared to the parent rocks, particularly in the lower part of horizon B in Mamasa profile and in horizon B2 in Palu profile. This suggests that REE-bearing accessory minerals may be resistant against weathering and may remain as residual phase in the weathered crusts. The normalized isocon diagram shows that the mass balance of major and REE components between each horizon in Mamasa and Palu weathering profile are different. The positive Ce anomaly in the horizon A of Mamasa profile indicated that Ce is rapidly precipitated during weathering and retain at the upper soil horizon.

关键词： rare earth element geochemistry weathered crust granitic rock Sulawesi Indonesia.

Geochemical and stable isotopic studies of Gulf of Suez’s hot springs,Egypt

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Chinese Journal Of Geochemistry 2012年第2期31卷 120-127页

作者： Mohamed Abdel Zaher Hakim Saibi Sachio Ehara Laboratory of Geothermics Department of Earth Resources EngineeringFaculty of EngineeringKyushu University Nathional Research Institute of Astronomy and Geophysics Laboratory of Exploration Geophysics Department of Earth Resources EngineeringFaculty of EngineeringKyushu University

The Gulf of Suez region is one of the most interesting geothermal areas in Egypt because of the high temperatures of its *** eastern and western shores of the Gulf of Suez are characterized by superficial thermal manifestations including a cluster of hot springs with varied *** of deuterium and oxygen-18 concentrations in thermal waters have been used to aid in describing the source of recharge in the Gulf of Suez hot *** and geochemical data for the Gulf of Suez thermal waters suggest that recharge to the hot springs may not be entirely from the Gulf of Suez water,but possibly from the meteoric water that comes from areas of higher altitude surrounding the hot springs.

关键词：地球化学资料苏伊士湾稳定同位素温泉水埃及高海拔地区海湾地区大气降水

Endogenous/exogenous dual stimulation“ROS engineering”amplification combined with autophagy-augmented for efficient ferroptosis therapy

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Nano Research 2025年第1期18卷 597-606页

作者： Pengye Du Pengpeng Lei Yuan Liang Ran An Yi Wei Shuyu Liu Jianhao Zheng Hongjie Zhang State Key Laboratory of Rare earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and engineering University of Science and Technology of ChinaHefei 230026China department of Chemistry Tsinghua UniversityBeijing 100084China

“Reactive oxygen species(ROS)engineering”is one of the most promising anti-tumor treatments developed in recent *** explosion of ROS will cause oxidative stress,thereby inducing tumor cell ***,ROS accumulation in tumor cells is eliminated by endogenous cellular self-regulation *** this work,a kind of endogenous/exogenous dual stimulation nanoagent noted as UMZC is *** reaction occurs between NH_(2)-MIL-88B(Fe)contained in UMZC and the overexpression of endogenous H_(2)O_(2)to generate ROS,amplified by endogenous H_(2)S of colon tumor *** addition,NH_(2)-MIL-88B(Fe)also functions to deplete glutathione(GSH)for stopping it from consuming *** nanoparticles at the core of UMZC convert near-infrared into visible light,which excites zinc phthalocyanine to initiate the photochemical reaction that generates more ROS,thus alleviating the lack of tissue penetration depth for visible *** agonist chitosan oligosaccharides induce enhancement of cellular autophagy for disrupting cellular metabolic stress and the resistance to oxidative stress of tumor cells,allowing“ROS engineering”to fully exert anti-tumor *** of ROS generation,GSH depletion,and induced cellular autophagy caused by nanoagents have promoting effects on the occurrence of ***,the nanoagents show the ability to effectively treat colon tumors.

关键词： reactive oxygen species(ROS)engineering upconversion nanoparticles cellular autophagy ferroptosis tumor therapy

Airflow adjustment and minimization of the air power of ventilation network

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Journal of Coal Science & engineering(China) 2011年第3期17卷 237-242页

作者： INOUE Masahiro YANG Wen-yu department of earth resources engineering Kyushu University Japan

It is often required to know which roadway （adjustment roadway） resistances and how much values of the resis- tances should be changed to make the airflow rates in roadways （target roadways） to certain required values in the practice of mine ventilation. In this case, the airflow rates of the target roadways and the resistances of the roadways other than the ad- justment roadways are the given conditions and the resistances of the adjustment roadways are the solutions to be found. No straightforward method to solve the problem has been found up to now. Therefore, trial and error method using the ventilation network analysis program is utilized to solve the problem so far. The method takes long calculation time and the best answer is not necessarily obtained. The authors newly defined ＂airflow element＂ as an element of the ventilation network analysis. The resistances that satisfy the airflow requirements can be calculated straight forwardly by putting the function of the airflow element into the ventilation network analysis. The air power required for the ventilation can be minimized while meeting the airflow requirements by the advanced application of the method. The authors made the computer program fulfill the method. The program was applied to actual ventilation network and it was found that the method is very practical and the time required for the analysis is short.

关键词： airflow adjustment mine ventilation airflow resistance optimization

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li Peng Ai Wanrong Guo Tuo Zheng College of Materials Science and engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

A hydrochemical study of the Hammam Righa geothermal waters in north-central Algeria

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Acta Geochimica 2016年第3期35卷 271-287页

作者： Mohamed Belhai Yasuhiro Fujimitsu Fatima Zohra Bouchareb-Haouchine Abdelhamid Haouchine Jun Nishijima department of earth resources engineering GraduateSchool of EngineeringKyushu UniversityFukuoka 819-0395Japan department of earth resources engineering Faculty ofEngineeringKyushu UniversityFukuoka 819-0395Japan Laboratoire de Geo-Environnement FSTGAT/USTHB BP 32El-Alia16000 AlgiersAlgeria

This study focuses on the hydrochemical characteristics of 47 water samples collected from thermal and cold springs that emerge from the Hammam Righa geothermal field, located in north-central Algeria. The aquifer that feeds these springs is mainly situated in the deeply fractured Jurassic limestone and dolomite of the Zaccar Mount. Measured discharge temperatures of the cold waters range from 16.0 to 26.5 ℃ and the hot waters from 32.1 to 68.2 ℃. All waters exhibited a near-neutral pH of 6.0-7.6. The thermal waters had a high total dis- solved solids （TDS） content of up to 2527 mg/l, while the TDS for cold waters was 659.0-852.0 mg/l. Chemical analyses suggest that two main types of water exist： hot waters in the upflow area of the Ca-Na-SO4 type （Ham- mam Righa） and cold waters in the recharge zone of the Ca-Na-HCO3 type （Zaccar Mount）. Reservoir tempera- tures were estimated using silica geothermometers and fluid/mineral equilibria at 78, 92, and 95℃ for HR4, HR2, and HRI, respectively. Stable isotopic analyses of the δ18O and δD composition of the waters suggest that the thermal waters of Hammam Righa are of meteoric origin. We conclude that meteoric recharge infiltrates through the fractured dolomitic limestones of the Zaccar Mount and is conductively heated at a depth of 2.1-2.2 km. The hotwaters then interact at depth with Triassic evaporites located in the hydrothermal conduit （fault）, giving rise to the Ca-Na-SO4 water type. As they ascend to the surface, the thermal waters mix with shallower Mg-rich ground- water, resulting in waters that plot in the immature water field in the Na-K-Mg diagram. The mixing trend between cold groundwaters from the recharge zone area （Zaccar Mount） and hot waters in the upflow area （Hammam Righa） is apparent via a chloride-enthalpy diagram that shows a mixing ratio of 22.6 〈 R 〈 29.2 %. We summa- rize these results with a geothermal conceptual model of the Hammam Righa geothermal field.

关键词： Thermal waters North-central Algeria Geochemistry Geothermometry Geothermal conceptualmodel Cold groundwaters

Carbon-supported CeNCl as an efficient catalyst for CO_(2)cycloaddition

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Nano Research 2025年第1期18卷 157-163页

作者： Li Liu Lingling Zhang Xiang Chu Baokang Geng Huilin Wang Zongxiang Li Xiao Wang Shuyan Song Hongjie Zhang School of Applied Chemistry and engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Rare earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Sinocare Incorporation Changsha 410221China department of Chemistry Tsinghua UniversityBeijing 100084China

The cycloaddition reaction of CO_(2)with epoxide not only effectively reduces the concentration of CO_(2)in the atmosphere,but also has excellent industrial application value and up to 100%atom utilization,but there are difficulties in separation and recovery of traditional homogeneous catalysts,harsh reaction conditions of traditional heterogeneous catalysts,and activation of CO_(2)*** this paper,an easily synthesized heterogeneous catalyst CeNCl/C was used to catalyze the cycloaddition reaction of CO_(2)with styrene oxide,with a high yield of 92.7%,a high selectivity of 96.7%,a turnover numbers(TON)value of 349,and a good stability demonstrated in six cycle tests(equivalent to 216 h of testing).Through comprehensive studies,it was shown that CeNCl/C contains Lewis acid-base centers as active centers,which can effectively reduce the energy barrier required for ring opening of the reaction substrate,enhance the adsorption and activation of CO_(2),and promote the formation of intermediates,which led to the acquisition of excellent catalytic activity.

关键词： CO_(2)cycloaddition heterogeneous catalysis CeNCl Lewis acid/base

Surface-borehole electric potential survey in layered media and its applications

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Journal of Central South university 2012年第4期19卷 1109-1115页

作者：苏本玉 Y.FUJIMITSU 宋建勇 department of earth resources engineering Graduate School of EngineeringKyushu University744 MotookaNishi-kuFukuoka819-0395Japan department of earth resources engineering Faculty of EngineeringKyushu University744 MotookaNishi-kuFukuoka819-0395Japan Research Institute of Petroleum Exploration and Development Petorchina

The method in which a source is set on the surface and electric potential is received in the borehole is called surface-borehole electric potential technique. Technique of surface-borehole electric potential was employed to study electric response of layered formation. The electric potential was obtained by solving Poisson equation with finite difference method. In the course of calculation, forward modeling wilth finite difference method was realized by adopting bandwidth non-zero storage technique and the incomplete Cholesky conjugate gradient method. The results show that method of surface-borehole can acquire anomalous electric potential corresponding tc geo-electric layers. In addition, application of appropriate mathematical operator can improve the resolution. Moreover, overburden low resistivity layers have severe influence on measuring results of surface-borehole electric potential. However, bottom low resistivity layers play a positive role in the measurement.

关键词： surface-borehole electric potential finite difference method forward modeling layered media

Compositional modeling and simulation of dimethyl ether (DME)-enhanced waterflood to investigate oil mobility improvement

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Petroleum Science 2018年第2期15卷 297-304页

作者： Jinhyung Cho Tae Hong Kim Kun Sang Lee department of earth resources and Environmental engineering Hanyang University

Dimethyl ether （DME） is a widely used industrial compound, and Shell developed a chemical EOR technique called DME- enhanced waterflood （DEW）. DME is applied as a miscible solvent for EOR application to enhance the performance of conventional waterflood. When DME is injected into the reservoir and contacts the oil, the first-contact miscibility process occurs, which leads to oil swelling and viscosity reduction. The reduction in oil density and viscosity improves oil mobility and reduces residual oil saturation, enhancing oil production. A numerical study based on compositional simulation has been developed to describe the phase behavior in the DEW model. An accurate compositional model is imperative because DME has a unique advantage of solubility in both oil and water. For DEW, oil recovery increased by 34% and 12% compared to conventional waterflood and CO2 flood, respectively. Compositional modeling and simulation of the DEW process indicated the unique solubility effect of DME on EOR performance.

关键词： Dimethyl ether (DME) DME-enhanced waterflood (DEW) Solubility Oil mobility