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Low-temperature NH_(3) abatement via selective oxidation over a supported copper catalyst with high Cu^(+) abundance

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Journal of Environmental Sciences 2024年第9期143卷 12-22页

作者： Zhiming Yang Lin Peng Leneng Yang Mingli Fu Daiqi Ye peirong chen Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control National Engineering Laboratory for VOCs Pollution Control Technology and EquipmentSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Guangdong chengyi Environmental Technology Corp. Shaoguan 512158China

Selective catalytic NH_(3)-to-N_(2) oxidation(NH_(3)-SCO)is highly promising for abating NH_(3) emissions slipped from stationary flue gas after-treatment devices.Its practical application,however,is limited by the non-availability of low-cost catalysts with high activity and N_(2) selectivity.Here,using defect-rich nitrogen-doped carbon nanotubes(NCNT-AW)as the support,we developed a highly active and durable copper-based NH_(3)-SCO catalyst with a high abundance of cuprous(Cu^(+))sites.The obtained Cu/NCNT-AW catalyst demonstrated outstanding activity with a T_(50)(i.***.the temperature to reach 50% NH_(3) conversion)of 174℃ in the NH_(3)-SCO reaction,which outperformed not only the Cu catalyst supported on N-free O-functionalized CNTs(OCNTs)or NCNT with less surface defects,but also those most active Cu catalysts in open literature.Reaction kinetics measurements and temperature-programmed surface reactions using NH_(3)as a probe molecule revealed that the NH_(3)-SCO reaction on Cu/NCNT-AW follows an internal selective catalytic reaction(i-SCR)route involving nitric oxide(NO)as a key intermediate.According to mechanistic investigations by X-ray photoelectron spectroscopy,Raman spectroscopy,and X-ray absorption spectroscopy,the superior NH_(3)-SCO performance of Cu/NCNT-AW originated from a synergy of surface defects and N-dopants.Specifically,surface defects promoted the anchoring of Cu O nanoparticles on N-containing sites and,thereby,enabled efficient electron transfer from N to Cu O,increasing significantly the fraction of SCR-active Cu^(+)sites in the catalyst.This study puts forward a new idea for manipulating and utilizing the interplay of defects and N-dopants on carbon surfaces to fabricate Cu^(+)-rich Cu catalysts for efficient abatement of slip NH_(3)emissions via selective oxidation.

关键词： NH_(3)-SCO XANES Localized etching N-doping N_(2) selectivity i-SCR

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Efficient NO_x abatement by passive adsorption over a Pd-SAPO-34 catalyst prepared by solid-state ion exchange

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Chinese Chemical Letters 2024年第4期35卷 210-213页

作者： Linhui Liu Wuwan Xiong Mingli Fu Junliang Wu Zhenguo Li Daiqi Ye peirong chen National Engineering Laboratory for VOCs Pollution Control Technology and Equipment Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution ControlSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China National Engineering Laboratory for Mobile Source Emission Control Technology China Automotive Technology&Research Center Co.Ltd.Tianjin 300300China

Palladium-exchanged chabazite(Pd-CHA) zeolites as passive NO_x adsorbers(PNAs) enable efficient purification of nitrogen oxides(NO_x) in cold-start diesel exhausts. Their commercial application, however,is limited by the lack of facile preparation method. Here, high-performance CHA-type Pd-SAPO-34 zeolite was synthesized by a modified solid-state ion exchange(SSIE) method using PdO as Pd precursor,and demonstrated superior PNA performance as compared to Pd-SAPO-34 prepared by conventional wetchemistry strategies. Structural characterization using Raman spectroscopy and X-ray diffraction revealed that the SSIE method avoided water-induced damage to the zeolite framework during Pd loading. Mechanistic investigations on the SSIE process by in situ infrared spectroscopy and X-ray photoelectron spectroscopy disclosed that, while PdO precursor was mainly converted to Pd^(2+) cations coordinated to the zeolite framework by consuming the-OH groups of the zeolite, a portion of PdO could also undergo thermal decomposition to form highly dispersed Pd~0 clusters in the pore channels. This simplified and scalable SSIE method paves a new way for the cost-effective synthesis of defect-free high-performance Pd-SAPO-34 zeolites as PNA catalysts.

关键词： Pd-SAPO-34 Passive NO_x adsorber Pd loading Solid-state ion exchange Pd transformation

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Petrogenesis of Early Cretaceous adakitic granodiorite: Implication for a crust thickening event within the Cathaysia Block, South China

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Science China Earth Sciences 2017年第7期60卷 1237-1255页

作者： SUN LiQiang LING HongFei ZHAO KuiDong chen peirong chen WeiFeng SUN Tao SHEN WeiZhou HUANG GuoLong State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University State Key Laboratory of Geological Processes and Mineral Resources and Collaborative Innovation Center for Exploration of Strategic Mineral Resources Faculty of Earth Resource China University of Geosciences Research Institute No.290 China National Nuclear Corporation

Adakitic rocks in continental settings are commonly considered to be formed by partial melting of thickened or delaminated lower crust. Investigations on this kind of rocks can provide important information about crustal evolution complementary to information from other rocks. This paper reports adakitic granodiorite of the Lingxi pluton in the interior of the Cathayisa Block. LA-ICP-MS zircon U-Pb dating shows that it was formed in the late Early Cretaceous(100±1 Ma). The granodiorite has geochemical features of adakitic rocks derived from partial melting of the thickened lower crust, e.g., high SiO2(mainly ranging from 64.4 to 68.9 wt.%) and Sr(624–894 ppm) contents, Sr/Y(49.9–60.8) and La/Yb(23.4–42.8) values, low Y(10.3–17.1 ppm), Ni(5.62–11.8 ppm) and MgO(mostly from 0.86 wt.% to 1.57 wt.%) contents and weak Eu anomaly. It has initial 87Sr/86 Sr ratios of 0.7086–0.7091, εNd(t) values of.6.2 to.5.9 and zircon εHf(t) values mostly of.10.1 to.7.6. Based on the geochemical characteristics and simple modelling, it is suggested that the most likely generation mechanism of the Lingxi granodiorite is partial melting of a thickened Proterozoic lower continental crust at a pressure ≥12 kbar(or crust thickness ≥40km), leaving a garnet-bearing amphibolite residue. Combining our results and previous studies of the tectonic evolution of the Cathaysia Block, we propose that the crust was thickened to over 40 km by a compressive event occurring during the late Early Cretaceous, which is supported by the observation that there is an angular unconformity between the Upper Cretaceous Series and the early Lower Cretaceous or the Jurassic rocks. After this event, the Cathaysia Block experienced a lithospheric extension and thinning probably driven by the high-angle paleo-Pacific subduction. With the attenuation of lithosphere, the lower crust was heated to partial melting by upwelling asthenospheric materials, resulting in generation of the Lingxi granodiorite and other coeval granitoids in the Cathaysia Block. This study provid

关键词：早白垩世晚期花岗闪长岩华夏地块地壳增厚中国南方地区事件锆石U-Pb定年岩石圈伸展减薄

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Single Zircon LA-ICP-MS U-Pb Dating of the Guandimiao and Wawutang Granitic Plutons in Hunan,South China and Its Petrogenetic Significance

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Acta Geologica Sinica(English Edition) 2007年第1期81卷 81-89页

作者： chen Weifeng chen peirong ZHOU Xinmin HUANG Hongye DING Xing SUN Tao The Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 No. 230 Research Institute CNNC Changsha Hunan 410011

The Guandimao and Wawutang plutons are located at the center of Hunan, South China. The former is mainly composed of biotite monzonitic granites/granodiorites and two-mica monzonltic granites, but the latter only consists of biotite monzonitic granites. The zircon ages of 203.0±1.6 Ma （biotite monzonitic granites） and 208.0-23.2 Ma （two-mica monzonltic granites） for the Guandimao pluton and 204±3 Ma for the Wawutang pluton obtained with the LA-ICP-MS U-Pb dating indicate that they were formed during the late Indosinian. In consideration of other geochronological data from Indosinian rocks of South China and adjacent regions, it is inferred that the two plutons were derived from crustal materials by decompressional melting in a post-collisional tectonic setting during spontaneous thinning of the thickened curst. Moreover, the inherited zircon age of 1273±57 Ma from the Wawutang pluton indicates that the source of the two plutons is related to the early Proterozoic crustal basement.

关键词： zircon LA-ICP-MS U-Pb dating granite Indosinian movement CL images

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Timing of hydrothermal activity associated with the Douzhashan uranium-bearing granite and its significance for uranium mineralization in northeastern Guangxi, China

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Chinese Science Bulletin 2013年第34期58卷 4319-4328页

作者： HU Huan WANG Rucheng chen WeiFeng chen peirong LING HongFei LIU GuoNing State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University

The Miaoershan uranium(U)ore field in northeastern Guangxi is one of the important granite-related U deposits in south China and is closely related to the Douzhashan U-bearing granite.The Douzhashan granite contains primary U-rich accessory minerals,including monazite(UO2=0.98-1.75 wt%)and xenotime(UO2=1.48-6.14 wt%).Primary monazite and xenotime yield chemical ages of 231±28 Ma and 230±38 Ma by electron microprobe analysis and U-Pb isotopic ages of 220±6 Ma and 211±7 Ma by laser ablation-inductively coupled-mass spectrometry respectively.These ages demonstrate that the Douzhashan granite formed during the period of Indosinian magmatic activity.Back scattered electron imaging shows that monazite and xenotime are commonly altered to assemblages of low-U synchisite and apatite,which was associated with loss of U to hydrothermal fluids.U-Th-Pb analyses of secondary apatite yielded a chemical age of 136±17 Ma,which corresponds to the timing of Cretaceous-Tertiary crustal extension in south China.We suggest that the heat and CO2required for mineralization was the result of Yanshanian crustal extension,and that this triggered the breakdown of U-rich accessory minerals in the Douzhashan U-bearing granite.Uranium remobilization from the Douzhashan granite provided materials for mineralization within the granite and/or surrounding country rocks.Therefore,a combination of Indosinian compression and Yanshanian extensional overprint produced the hydrothermal U deposits associated with the Douzhashan granite.

关键词：花岗岩型铀矿中国南方东北部含铀热液活动成矿意义广西时间

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中国城市生态效率的空间收敛性分析:基于地方政府竞争的视角

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Journal of Resources and Ecology 2024年第1期15卷 90-104页

作者：陈培荣尹向飞卢茗轩湖南财政经济学院经济学院长沙410205 湖南财政经济学院数学与统计学院长沙410205 湖南财政经济学院工商管理学院长沙410205

生态环境区域协同治理是促进区域可持续发展的重要途径,而地方政府竞争是中国区域生态环境治理过程中容易被忽视的体制性因素。选取2006–2018年中国278个地级市的面板数据,运用空间收敛回归模型和中介效应模型,从地方政府竞争的角度分... 详细信息

生态环境区域协同治理是促进区域可持续发展的重要途径,而地方政府竞争是中国区域生态环境治理过程中容易被忽视的体制性因素。选取2006–2018年中国278个地级市的面板数据,运用空间收敛回归模型和中介效应模型,从地方政府竞争的角度分析城市生态效率的空间收敛性及其影响机制。结果表明:首先,城市生态效率呈现收敛趋势,空间因素是影响城市生态效率收敛的关键因素;其次,地方政府竞争作为一种制度因素,在促进城市生态效率空间收敛的过程中发挥着重要作用,并且行政距离邻近竞争比地理距离邻近竞争的效应更强,其竞争压力程度每增加1个百分点,城市生态效率就增加0.114个百分点。再次,地方政府竞争导致了严格的环境规制政策,这些规制政策整体上促进了城市生态效率的改善,从而缩小了落后城市与先进城市的差距。最后,地方政府通过环境规制政策对城市生态效率产生异质性影响。具体而言,在地方政府间的竞争压力下,东部和环保重点地区城市的环境规制改善了生态效率,而中部和非环保重点地区城市的效果则相反。本研究的上述结果表明,如果进一步将城市生态效率引入地方官员行政绩效评价指标体系,可以通过生态竞争缩小地区之间的区域差距。

关键词：空间收敛城市生态效率地方政府竞争环境规制

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Composition variations of the Sinian-Cambrian sedimentary rocks in Hunan and Guangxi and their tectonic significance

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Science China Earth Sciences 2013年第11期56卷 1899-1917页

作者： WANG PengMing YU JinHai SUN Tao SHI Yu chen peirong ZHAO KuiDong chen WeiFeng LIU Qian State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University

This paper reports the geochemical and zircon U-Pb dating data of the Sinian to Cambrian low-grade metamorphic rocks in the Miaoer Mountain area,Guangxi and the Jinjiling area,Hunan Province.Petrographic and geochemical features indicate that protoliths of these metamorphic rocks are clastic sedimentary rocks with medium weathering,which were formed in the passive continental margin.Geochemistry and zircon U-Pb ages indicate that the Sinian and Cambrian sedimentary rocks in the Jinjiling area have similar detritus components,which are characterized by abundant Grenvillian detrital zircons,suggesting a close affinity with the Cathaysia Block.The Cambrian sedimentary rocks in the Miaoer Mountain area have similar geochemistry and zircon geochronology to those in the Jinjiling area,showing an affinity with the Cathaysia Block.However,the Sinian sedimentary rocks in the Miaoer Mountain area show different geochemical features from the Cambrian sedimentary rocks and those in the Jinjiling area,and are characterized by abundant 840–700 Ma detrital zircons and less^2.0 Ga ones,showing a close affinity with the Yangtze Block.These variations suggest that the Jinjiling area continuously accepted the fragments from the Cathaysia from the Sinian to the Cambrian,whereas the provenance of the Miaoer Mountain sedimentary basin changed from the Yangtze Block to the Cathaysia Block during this interval.This change implies a tectonic movement,which caused the further sinking of the basin in the Miaoer Mountain area and northwestward transferring of the basin center before the Middle Cambrian,so that the Miaoer Mountain basin received the detritus from the Cathaysia Block in the Middle Cambrian.This fact also proves that the Yangtze and Cathaysia blocks have converged at least in Middle Cambrian,and the southwestern boundary between them is located between the Miaoer Mountain and Jinjiling areas.

关键词：碎屑沉积岩震旦系寒武纪湖南省组成变化构造意义广西地球化学特征

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我国华南地区家禽配合饲料中3种真菌毒素污染现状分析

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动物营养学报 2024年第1期36卷 672-680页

作者：曾睿陈佩榕王琼珊王富华赵亚荣广东省农业科学院农业质量标准与监测技术研究所广州510640 农业农村部农产品质量安全风险评估实验室(广州) 广州510640 农业农村部农产品质量安全检测与评价重点实验室广州510640 广东省农产品质量安全风险评估重点实验室广州510640 广东食品药品职业学院广州510520

本试验旨在通过分析我国华南地区家禽配合饲料中柄曲霉素(STC)、赭曲霉毒素A(OTA)、玉米赤霉烯酮(ZEA)的污染情况,为真菌毒素风险评估提供数据支撑。从华南地区(广东省、海南省、广西壮族自治区)采集家禽配合饲料样品232份,经含20%水的... 详细信息

本试验旨在通过分析我国华南地区家禽配合饲料中柄曲霉素(STC)、赭曲霉毒素A(OTA)、玉米赤霉烯酮(ZEA)的污染情况,为真菌毒素风险评估提供数据支撑。从华南地区(广东省、海南省、广西壮族自治区)采集家禽配合饲料样品232份,经含20%水的甲醇提取,氯化钠和无水硫酸镁盐析后,加入N-丙基乙二胺(PSA)和C 18吸附杂质,上清液过膜后进行高效液相色谱串联质谱(HPLC-MS/MS)分析,通过基质标准曲线进行定量。分别采用卡方检验和非参数检验比较不同地区家禽配合饲料中STC、OTA、ZEA的检出率和含量。结果显示:3种真菌毒素在各自线性范围内线性关系良好,相关系数≥0.99,检出限和定量限分别为0.02~0.18μg/kg和0.07~0.59μg/kg,在低、中、高3个加标水平下,3种真菌毒素的平均回收率为83.0%~98.9%,精密度为0.8%~8.2%,日间差和日内差均<20%。232份家禽配合饲料样品中,ZEA检出率最高(100.0%),其次为STC(70.3%)、OTA(22.0%)。其中,海南省样品中STC的检出率显著高于其他地区(P<0.05)。本试验开发的方法操作简单、灵敏度高,适用于饲料中ZEA、OTA和STC的同时检测分析;我国华南地区家禽配合饲料尽管总体污染水平较低,但真菌毒素污染情况普遍,应引起重视。

关键词：真菌毒素饲料华南地区 HPLC-MS/MS

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Estimate of influence of U-Th-K radiogenic heat on cooling process of granitic melt and its geological implications

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Science China Earth Sciences 2007年第5期50卷 672-677页

作者： ZHANG BangTong WU JunQi LING HongFei chen peirong The State Key Laboratory for Mineral Deposits Research and Department of Earth Sciences Nanjing UniversityNanjing 210093China

The U-Th-^(40)K concentrations of granite are on 1―2 orders of magnitude greater than those of basal- tic-ultrabasic rocks. Radiogenic heat of a granitic melt has significant influence on the cool- ing-crystallization period of the melt. In this paper we derived a formula to calculate prolongation period (tA) of cooling-crystallization of a granitic melt caused by radiogenic heat. Calculation using this for- mula and radioactive element concentrations (U=5.31×10-6; Th=23.1×10-6; K=4.55%) for the biotite adamellite of the Jinjiling batholith shows that the tA of the adamellite is 1.4 times of the cooling period of the granitic melt without considering radiogenic heat from the initial temperature (Tm=960℃) to crystallization temperature (Tc=600℃) of the melt. It has been demonstrated that the radiogenic heat produced in a granitic melt is a key factor influencing the cooling-crystallization process of the granitic melt, and is likely one of the reasons for inconsistence between emplacement ages and crystallization ages of many Meso-Cenozoic granitoids.

关键词： U-Th-40K radiogenic heat granitic melt cooling-crystallization period emplacement-crystallization time difference

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Geochemical characteristics of Cretaceous basaltic rocks in South China and constraints on Pacific plate subduction

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Science China Earth Sciences 2005年第12期48卷 2104-2117页

作者： chen Weifeng chen peirong XU Xisheng ZHANG Min The State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China The State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China The State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China The State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China

Middle-Late Cretaceous Basaltic rocks (85―110 Ma) are distributed in the contemporaneous downfaulted red basins and volcanic-sedimentary basins in South China (including Hunan, Jiangxi, Guangdong, Fujian, Zhejiang provinces). They are geographically divided into two groups delimited by Wuyishan Range, namely the west area basaltic rocks (WABs) distributing over the west of Wuyishan Range and the east area basaltic rocks (EABs) distributing over the east of Wuyishan Range, and observed having distinct geochemical and isotopic characters. WABs are characterized by relatively low in K2O (0.44%―3.17%), alkalis (K2O+Na2O= 3.27%―6.80%) and Al2O3 (13.08%―16.75%) contents, but high in MgO (5.13%―8.78%) and TiO2 (1.12%―3.35%) contents. WABs are similar to ocean-island basalts (OIB) or intraplate basalts on trace elements and isotopes: no negative Nb and Ta anomalies, relatively low ∑REE (74.66 μg/g―287.72 μg/g) and LaN/YbN (4.49―22.10), low (87Sr/86Sr)i (average ratio is 0.704679), high εNd(t) (?1.81―8.00). In contrast, EABs display relatively high in K2O (0.55%―4.86%), alkalis (K2O+Na2O=2.95%―7.55%) and Al2O3 (15.80%―21.10%) contents, but low in MgO (2.63%―6.28%) and TiO2 (1.19%―1.86%) contents, strong negative Nb and Ta anomalies, enrichment in LILE (K, Rb, Ba and Th), relatively high ΣREE (79.68 μg/g―327.61 μg/g) and LaN/YbN (5.25―26.37), high (87Sr/86Sr)i (average ratio is 0.707658) and negative εNd(t) (?8.50― ?1.22), similar to that of IAB (island arc basalts) or CAB (continental arc basalts). Accordingly, WABs were probably generated under continental rifting tectonic setting related to asthenosphere upwelling, and hence their source was characterized by mixing between EMⅡ with DM. Source of EABs may be enriched lithoshperic mantle which had ever undergone the metasomatism of fluid/melt derived from the subducted Pacific plate.This indicates that subduction of a paleo-Pacific plate (Kula) beneath the Eurasian continent had ever occurred during the late Mesozoic period, but the metasomatism resulted from the subducti

关键词： basalt, imprint of subducted plate, rifting, Cretaceous basins, South China.

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