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The Coexisting Clinopyroxene-Garnet Acidometer and Acidity Facies of Skarn deposits

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 299-308页

作者： Lin Wenwei institute of mineral {2., Chinese Academy of Geological Sciences, Beijing {3. linqun institute of mineral {2. Chinese Academy of Geological Sciences Beijing

On the basis of geological studies of skarn deposits in China and by using thermodynamic models of thesolid solution, the coexisting clinopyroxene-garnet pair in skarn deposits has been analysed and a coexistingclinopyroxene-garnet acidometer developed. They can be used to estimate the medium condition under whichthe skarn was formed. The research on the acidity for the formation of various metallic skarn deposits in Chinasuggests that skarns endowed with dissimilar types of {3.ization and occurring in diverse environments dif-fer in the acidity conditions for their formation and in the trend of acidity variation of ore-bearing fluid. This,coupled with the study of oxygen fugacity of coexisting {3.s, makes it possible to establish the oxygenfugacity-acidity facies of skarn deposits, which reflect the close genetic relationship between the metallizationand the formation of skarn.

关键词： OH The Coexisting Clinopyroxene-Garnet Acidometer and Acidity Facies of Skarn deposits

Rare Earth Elements in Manganese Nodules from the Central Pacific Ocean

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Acta Geologica Sinica(English Edition) 1992年第4期66卷 371-383页

作者： Guo Shiqin Sun Wenhong China Ocean mineral Resources Research and Developmetn Association institute of mineral {3., Chinese Academy of Geological Sciences liu linqun China Ocean mineral Resources Research and Development Association China

Manganese nodules in areas CP and CC of the central Pacific are rich in REE. Comparatively speaking,the REE contents of nodules in area CP are hihger than those in area CC; and the REE contents of nodulesfrom seamounts are higher than those of nodules from sea-floor plains and hills. Within the nodules, the REEshow a zonal distribution. The REE distribution patterns of the nodules are similar to those of the sedimentsand have a mirror image relationship with those of the sea water. Trivalent REE were not obviously differenti-ated when they entered into the nodules from the sea water.A major factor causing the difference of REE abundances between nodules and sediments is the redoxconditions. The redox intensity of the ocean floor of the Pacific is controlled mainly by Antarctic Bottom Wat-er(AABW), The iron-bearing facies in the nodules is the main carrier of REE.

关键词： manganese nodule rare earth element Pacific

Origin and tectonic setting of low-Si alkaline magma

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Science China Earth Sciences 2024年第5期67卷 1417-1435页

作者： Qiushi ZHOU rui WANG State Key Laboratory of Geological Processes and mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China

Despite of the relatively rare occurrence of alkaline igneous rocks on Earth, they are the most diverse group of igneous rocks due to variations in their mineral assemblages and geochemical compositions. Alkaline igneous rocks are generally characterized by Si undersaturation, and K-Na(and in some cases C) enrichment. Although there is no unified alkaline igneous rock classification scheme, diagrams such as total alkalis-SiO_(2. or K_(2.O-SiO_(2. can be used to classify alkaline igneous rocks. The origins of silica-saturated alkaline rocks(SiO_(2.>52.wt.%) are relatively complex because multiple episodes of magmatism are often involved, therefore most studies have focused on the origins of silica-undersaturated alkaline *** experimental petrological studies have been conducted in the past few decades. Initially, it was considered that enrichment of trace elements was only achieved by low-degree partial melting of mantle peridotite, but the experimental melts could not reproduce the geochemical composition of natural alkaline igneous rocks. Subsequent studies have focused on carbonate-bearing eclogites that represent the average component of subducted oceanic crust. Although experimental studies indicate that silica-undersaturated and alkali-oversaturated melts can be generated from eclogites, some studies have considered that natural silica-undersaturated alkaline igneous rocks are the result of multi-stage source enrichment by incompatible elements. Low-degree partial melts of the mantle can be emplaced in the lithospheric mantle, forming veins consisting of phlogopite, amphibole, and pyroxene. Melting experiments including these components show that the produced melts better reproduce the naturally occurring silica-undersaturated alkaline magmas. Silica-deficient alkaline igneous rocks occur in various tectonic settings. Those in intraplate and divergent settings(i.e., mainly continental rifts) normally involve contributions from recycled components su

关键词： Alkaline igneous rock Tectonic setting Petrogenesis Big data

Minerogenetic Model for Two Types of Fluorite deposits in Southeastern China

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 75-88页

作者： Li Changjiang Jiang Xuliang Zhejiang institute of Geology and mineral Resources, Hangzhou {2. {3. Zhejiang institute of Geology and mineral Resources Hangzhou

On the basis of the studies of field geology, strontium, hydrogen and oxygen isotopes and REEgeochemistry, coupled with the dating of mineralization, the authors suggest a minerogenetic model of circula-tion and drawing of Late Cretaceous geothermal waters for the fluorite deposits in southeastern China. Thismodel includes two types of mechanism: 1) the leaching-out and drawing through deep circulation of thegeothermal water, and 2. the leaching-out and drawing through shallow circulation of the water. The fluoritemineralization of Mesozoic volcanic rock terrain is related mainly to the former mechanism, with the mineraliz-ing material coming chiefly from the Precambrian metamorphic rocks of the basement underlying the hostrocks; while that of Yanshanian granite terrain is associated with the latter mechanism, with the mineralizingmaterial derived primarily from the host granites and sedimentary rocks.

关键词： Minerogenetic Model for Two Types of Fluorite deposits in Southeastern China

Mechanisms of vacuolar phosphate efflux supporting soybean root hair growth in response to phosphate deficiency

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Journal of Integrative Plant Biology 2024年第9期66卷 1983-1999页

作者： Zhong Shan Yanli Chu Guangfang Sun rui Chen Jun Yan Qiwei He Yingna liu Bin Wang Mingda Luan Wenzhi Lan School of Life Sciences Nanjing UniversityNanjing 210023China institute of Future Agriculture Northwest A&F UniversityYangling 712100China

Phosphorus is an essential macronutrient for plant growth and *** response to phosphate(Pi)deficiency,plants rapidly produce a substitutive amount of root hairs;however,the mechanisms underlying Pi supply for root hair growth remain ***,we observed that soybean(Glycine max)plants maintain a consistent level of Pi within root hairs even under external Pi *** therefore investigated the role of vacuole-stored Pi,a major Pi reservoir in plant cells,in supporting root hair growth under Pi-deficient *** findings indicated that two vacuolar Pi efflux(VPE)transporters,GmVPE1 and GmVPE2.remobilize vacuolar stored Pi to sustain cytosolic Pi content in root hair *** analysis showed that double mutants of GmVPE1 and GmVPE2.exhibited reduced root hair growth under low Pi ***,GmVPE1 and GmVPE2.were highly expressed in root hairs,with their expression levels significantly upregulated by low Pi *** analysis revealed that GmRSL2.ROOT HAIR DEFECTIVE 6-like 2.,a transcription factor involved in root hair morphogenesis,directly binds to the promoter regions of GmVPE1 and GmVPE2.and promotes their expressions under low Pi ***,mutants lacking both GmRSL2.and its homolog GmRSL3.exhibited impaired root hair growth under low Pi stress,which was rescued by overexpressing either GmVPE1 or *** together,our study has identified a module comprising vacuolar Pi exporters and transcription factors responsible for remobilizing vacuolar Pi to support root hair growth in response to Pi deficiency in soybean.

关键词： mineral deficiency remobilization root remodeling transcriptional regulation

Discovery of Fossil Charophytes from the Late Triassic Xujiahe Formation and Early Jurassic Lower Yimen Formation, Sichuan Province, and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 301-309,327页

作者： liu Junying Chen Zhongliang institute of Geology, Chinese Academy of Geological Sciences, Beijing Panxi Geological Party, Sichuan Bureau of Geology and {2. Resources, Xichang liu {2. institute of Geology Chinese Academy of Geological Sciences Beijing China

This paper describes the fossil charophytes collected from the Late Triassic Xujiahe Formation in Dazuand Early Jurassic Lower Yimen Formation in Xichang, Sichuan Province, and their significance. Up to now,papers dealing with fossil charophytes of the Late Triassic, especially of the Early Jurassic, have been rarelypublished. The description of the two new species of Porochara, P. dazuensis and P. xichangensis, and theirfossil assemblage not only provides an important basis for classification and correlation of red beds insouthwestern China but reveals for the first time the features of the charophyte flora of the Late Triassic-EarlyJurassic in the area, thus offering valuable data for the establishment of Triassic and Jurassic charophyte fossilzones in China.

关键词： Sichuan Late Triassic Early Jurassic charophyte fossil

Agronomic performances of biodegradable and non-biodegradable plastic film mulching on a maize cropping system in the semi-arid Loess Plateau,China

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Pedosphere 2024年第1期34卷 88-96页

作者： Hao ZHANG Mengqiong CHEN ruiquan QIAO Fan DING Hao FENG rui JIANG Research Center for Cultural Landscape Protection and Ecological Restoration China-Portugal Belt and Road Cooperation Laboratory of Cultural Heritage Conservation ScienceGold Mantis School of ArchitectureSoochow UniversitySuzhou 215006China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of AgricultureCollege of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China College of Land and Environment Shenyang Agricultural UniversityShenyang 110866China institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China

Biodegradable plastic film mulch (PFM) is considered an alternative to non-biodegradable PFM to mitigate the negative impacts of residual ***,the agronomic performance of biodegradable PFM in comparison to non-biodegradable PFM still needs to be *** this study,we evaluated the effects of biodegradable and non-biodegradable PFM on soil physicochemical properties,microbial community,and enzyme activities,as well as maize growth *** and non-biodegradable PFM both increased soil temperature,water content,N content,and microbial biomass and maize yield by up to 3.%,but decreased soil enzyme activities as compared to no mulching (control,CK).Most soil physicochemical properties,microbial community,and enzyme activities were similar under non-biodegradable and biodegradable PFM at the early stages of maize ***,at the late stages,soil temperature,water content,mineral N,NO_(3.^(-)-N,ammonia monooxygenase (AMO) activity,and total phospholipid fatty acids (PLFAs) decreased under biodegradable PFM owing to film *** PFM increased soil temperature,water content,and total PLFAs at the early stages of maize growth but decreased soil mineral N and total PLFAs at the late stages,as compared to black *** soil temperature and N availability were the major factors affecting soil microbial community,microbial activity decreased after the fragmentation of biodegradable PFM,owing to the decreased soil temperature,water content,and mineral ***,biodegradable PFM could decrease NO_(3.^(-)-N accumulation in topsoil by decreasing N transformation due to the lower microbial and N-related enzyme (e.g.,AMO) activities,compared with non-biodegradable PFM,which may avoid negative environmental impacts,such as NO_(3.^(-)-N leaching or gas emission after *** yield,height,aboveground biomass,and N uptake under biodegradable PFM were similar to those under non-biodegradable PFM during maize growth,implying that biodegrad

关键词： black plastic film mulching enzyme activity film fragmentation microbial community phospholipid fatty acid white plastic film mulching

Seabed structures and foundations related to deep-sea resource development:A review based on design and research

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Deep Underground Science and Engineering 2024年第2期3卷 131-148页

作者： Shengjie rui Haojie Zhang Hang Xu Xing Zha Mengtao Xu Kanmin Shen Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhouChina Advanced Modelling Offshore EnergyNorwegian Geotechnical InstituteOsloNorway Geotechnical Technology Center(Overseas Engineering Center) PowerChina Huadong Engineering Corporation LimitedHangzhouChina

The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and *** infrastructures such as floating structures,seabed structures,and foundations have been developed to exploit these *** seabed structures and foundations can be mainly classified into three types:subsea production structures,offshore pipelines,and *** study reviewed the development,installation,and operation of these infrastructures,including their structures,design,installation,marine environment loads,and *** this basis,the research gaps and further research directions were explored through this literature ***,different floating structures were briefly analyzed and reviewed to introduce the design requirements of the seabed structures and ***,the subsea production structures,including subsea manifolds and their foundations,were reviewed and ***,the basic characteristics and design methods of deep‐sea pipelines,including subsea pipelines and risers,were analyzed and ***,the installation and bearing capacity of deep‐sea subsea anchors and seabed trench influence on the anchor were *** the review,it was found that marine environment conditions are the key inputs for any offshore structure *** fabrication,installation,and operation of infrastructures should carefully consider the marine loads and geological *** structures have their own mechanical *** fatigue and stability of pipelines mainly depend on the soil‐structure *** selection should consider soil types and possible trench *** focuses and research gaps can provide a helpful guide on further research,installation,and operation of deep‐sea structures and foundations.

关键词： anchors floating structures pipelines risers subsea foundations

甜酒曲发酵小米酒精饮料工艺优化及其品质分析

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食品工业科技 2024年第9期45卷 186-195页

作者：张瑞刘敬科刘俊利常世敏河北省农林科学院生物技术与食品科学研究所河北石家庄050000 河北工程大学生命科学与食品工程学院河北邯郸056038

为增加小米资源利用率,本文以小米为原料用甜酒曲发酵成小米酒精饮料,采用可溶性固形物、总酸及感官评分为综合评价指标,通过单因素实验和响应面试验研究小米酒精饮料的最佳工艺,并对其营养品质、抗氧化能力和挥发性风味物质进行测定。... 详细信息

为增加小米资源利用率,本文以小米为原料用甜酒曲发酵成小米酒精饮料,采用可溶性固形物、总酸及感官评分为综合评价指标,通过单因素实验和响应面试验研究小米酒精饮料的最佳工艺,并对其营养品质、抗氧化能力和挥发性风味物质进行测定。结果表明:甜酒曲添加量1%、发酵时间3.d、发酵温度3.0}为最佳。所得产品可溶性固形物为2..05%,总酸为19.3. g/L,感官评分为89.3.分,酒精度0.7%vol,黄酮含量66.78 mg/L,多酚含量65.13.mg/L。所测矿物质中钾含量最高,所测维生素中烟酰胺含量最高,DPPH自由基清除率73.19%,ABTS+自由基清除率3..2.%,羟自由基清除率53.72.。此外,共检测到46种挥发性风味物质,种类最多的为酯类和醇类,它们共同赋予小米酒精饮料特有的香气。该产品营养丰富且滋味浓郁、酸甜适中,可为开发以小米为原料的功能性食品提供理论参考。

关键词：小米甜酒曲发酵酒精饮料活性成分抗氧化挥发性风味

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