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INTERGROWTH-21^(st)标准评价胎儿宫内生长受限的临床价值 被引量:10
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作者 朱晨 任芸芸 吴江南 《复旦学报(医学版)》 CAS CSCD 北大核心 2017年第3期307-311,325,共6页
目的探讨INTERGROWTH-21^(st)标准评价胎儿宫内生长受限的应用价值。方法本研究为前瞻性队列研究。收集2015年3月至2016年3月在复旦大学附属妇产科医院建卡,进行常规产前检查并入院分娩的单胎妊娠孕妇。所有入选病例孕28周之后入组,每4... 目的探讨INTERGROWTH-21^(st)标准评价胎儿宫内生长受限的应用价值。方法本研究为前瞻性队列研究。收集2015年3月至2016年3月在复旦大学附属妇产科医院建卡,进行常规产前检查并入院分娩的单胎妊娠孕妇。所有入选病例孕28周之后入组,每4周做一次产前超声生长测量,直至分娩前。胎儿生长径线以INTERGROWTH-21^(st)标准计算Z-score值。分娩后随访新生儿体重等相关信息。应用Logistic回归方程建立预测公式。最后将新公式与Hadlock法预测IUGR的准确性进行对比。结果共收集符合入组条件的孕妇834例。排除失访143例后,得到对照组565例和IUGR组126例。新预测公式的敏感性、特异性、阳性预测值、阴性预测值、假阳性率、假阴性率分别为:88.9%、85.4%、57.7%、97.2%、14.6%、11.1%。Hadlock法预测的敏感性、特异性、阳性预测值、阴性预测值、假阳性率、假阴性率分别为:81.7%、82.7%、51.2%、95.3%、17.3%、18.3%。结论以INTERGROWTH-21^(st)标准计算Z-score建立新公式预测胎儿宫内生长受限的方法,与传统的Hadlock预测法相比,改善了产前诊断的敏感性和特异度,减少了假阳性和假阴性的病例,全面提高了超声预测胎儿宫内生长受限的准确性。 展开更多
关键词 intergrowth-21st Z-SCORE 胎儿宫内生长受限 超声生长测量 晚孕期
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Hydroisomerization performance of platinum supported on ZSM-22/ZSM-23 intergrowth zeolite catalyst 被引量:10
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作者 Chi Kebin Zhao Zhen +8 位作者 Tian Zhijian Hu Sheng Yan Lijun Li Tianshu Wang Bingchun Meng Xiangbin Gao Shanbin Tan Mingwei Liu Yanfeng 《Petroleum Science》 SCIE CAS CSCD 2013年第2期242-250,共9页
Hydroisomerization catalysts Pt/ZSM-22, Pt/ZSM-23, and Pt/ZSM-22/ZSM-23 were prepared by supporting Pt on ZSM-22, ZSM-23, and intergrowth zeolite ZSM-22/ZSM-23, respectively. The typical physicochemical properties of ... Hydroisomerization catalysts Pt/ZSM-22, Pt/ZSM-23, and Pt/ZSM-22/ZSM-23 were prepared by supporting Pt on ZSM-22, ZSM-23, and intergrowth zeolite ZSM-22/ZSM-23, respectively. The typical physicochemical properties of these catalysts were characterized by X-Ray Diffraction (XRD), N2 absorption-desorption, Pyridine-Fourier Transform Infrared (Py-FTIR), Transmission Electron Microscopy (TEM), X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM) and NH3- Temperature Programmed Desorption (NH3-TPD), and the performance of these catalysts in n-dodecane hydroisomerization was evaluated in a continuous down-flow fixed bed with a stainless steel tubular reactor. The characterization results indicated that the intergrowth zeolite ZSM-22/ZSM-23 possessed the dual structure of ZSM-22 and ZSM-23, and the catalyst Pt/ZSM-22/ZSM-23 had similar pores and weak acidity to Pt/ZSM-22 and Pt/ZSM-23 catalysts. Moreover, Pt/ZSM-22/ZSM-23 catalyst showed a high selectivity in hydroisomerization of long chain n-alkanes to mono-branched isomers. The evaluation results for n-dodecane hydroisomerization indicated that the activity of Pt/ZSM-22/ZSM-23 was the lowest, while the hydroisomerization selectivity was the highest among the three catalysts. The maximum yield of i-dodecane product was 68.3% over Pt/ZSM-22/ZSM-23 at 320 ℃. 展开更多
关键词 ZSM-22/ZSM-23 intergrowth zeolite platinum catalyst N-DODECANE HYDROISOMERIZATION
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Rainfall,Landslide and Debris Flow Intergrowth Relationship in Jiangjia Ravine 被引量:7
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作者 HU Mingjian WANG Ren SHEN Jianhua 《Journal of Mountain Science》 SCIE CSCD 2011年第4期603-610,共8页
Jiangjia Ravine is a world-famous debris flow valley in Dongchuan,Yunnan Province,China.Every year large numbers of landslides and collapses happened and caused enormous damages to people's properties and lives.Wi... Jiangjia Ravine is a world-famous debris flow valley in Dongchuan,Yunnan Province,China.Every year large numbers of landslides and collapses happened and caused enormous damages to people's properties and lives.With longtime observation and testing in Jiangjia Ravine we had found out one kind of special landslide which had the characteristics of landslide and collapse.Landslide and collapse supplied sufficient materials for debris flow.When a debris flow broke out,some kind of intergrowth existed among rainfall,landslide and debris flow.In order to study the intergrowth and some key parameters,we carried out artificial rainfall landslide tests and model experiments to observe the phenomena such as collapse,surface slide and surface flow.By observing the experimental phenomena and monitoring water contents,the transformation process among landslide deposits and debris flow under the condition of rainfall had been analyzed.Research results revealed the relationship of this kind of intergrowth among rainfall,landslide and debris flow in Jiangjia Ravine.Meanwhile,it was found that this kind of intergrowth relationship existed only when the moisture content was in a certain range.That is,the critical state seemed to be existed in the transformation process. 展开更多
关键词 LANDSLIDE DEBRIS-FLOW RAINFALL intergrowth Moisture Content Jiangjia Ravine
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Crossed intergrowth triggered TS-2 microsphere:Formation mechanism,modification and catalytic performance 被引量:3
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作者 Hao Xu Wenwen Tian +5 位作者 Liping Xu Xin Jin Teng Xue Li Chen Mingyuan He Peng Wu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第7期1109-1117,共9页
TS-2 microspheres,consisting of intergrown primary nanocrystals,was prepared by controlling the synthetic parameters.The effects of the amount of quaternary ammonium cations as structure-directing agent,H2O/Si ratio,t... TS-2 microspheres,consisting of intergrown primary nanocrystals,was prepared by controlling the synthetic parameters.The effects of the amount of quaternary ammonium cations as structure-directing agent,H2O/Si ratio,the presence of alcohol and the temperature were carefully investigated on the crystallization process.The high alkalinity was proved to be highly important for the preservation of the microsphere morphology initially formed,due to the unique intergrown stacking style.An alkali treatment with the aqueous solution of structure-directing agent,organic amine and ammonium salt and subsequent Na+ion-exchange were performed to enhance the catalytic activity of TS-2 microsphere in the cyclohexanone ammoximation reactions,with both the conversion and selectivity higher than 99%.In the continuous reaction,the TS-2 microspheres exhibited to be durable catalyst with potential application in industrial ammoximation processes. 展开更多
关键词 TITANOSILICATE TS-2 microsphere Crossed intergrowth Ammoximation reaction POST-TREATMENT
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Perpendicular intergrowth ZSM-5 plates with shortened 10-MR pores 被引量:3
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作者 Ensheng Zhan Zhiping Xiong +4 位作者 Yan Zhou Mingrun Li Pengfei Wang Weibin Fan Wenjie Shen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第7期1132-1139,共8页
ZSM-5 plates with a perpendicular intergrowth structure was synthesized by using a simple amine as the structure directing agent under hydrothermal conditions,in which the mother plate and the perpendicularly standing... ZSM-5 plates with a perpendicular intergrowth structure was synthesized by using a simple amine as the structure directing agent under hydrothermal conditions,in which the mother plate and the perpendicularly standing plates oriented along the(010)and(100)planes of MFI crystals,respectively.During the crystallization process,the mother plate was initially formed on the surface of the amorphous solid gel,while a set of parallel plates perpendicularly grew on its surface,via a homogeneous nucleation mechanism.The mother plate and the perpendicular plates had a similar thickness of 100-200 nm and were characterized by considerably shortened straight and zigzag 10 member ring pores,respectively.This unique intergrowth structure greatly facilitated the diffusion of the reactive molecules in HZSM-5 crystals during methanol conversion to hydrocarbons. 展开更多
关键词 ZSM-5 Plate structure Perpendicular intergrowth Channel length Hierarchical structure Molecule diffusion
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Intergrowth mechanism and morphology prediction of faceted Al_(3)Ni formed during solidification by a spatial geometric model 被引量:2
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作者 Zongye Ding Qiaodan Hu +6 位作者 Wenquan Lu Fan Yang Yihan Zhou Naifang Zhang Sheng Cao Liao Yu Jianguo Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第19期40-47,共8页
The interplay and intergrowth characteristic of faceted intermetallic compounds(IMCs)during solidification was originally investigated through the rod-like Al3 Ni crystals in the liquid Al/solid Ni interconnection by ... The interplay and intergrowth characteristic of faceted intermetallic compounds(IMCs)during solidification was originally investigated through the rod-like Al3 Ni crystals in the liquid Al/solid Ni interconnection by using synchrotron radiography,and the diversified 3-D morphologies were reconstructed by synchrotron tomography.A spatial geometric model was established to effectively predict the diversified growth patterns of two spatial crystals.For the two overlapping Al3 Ni crystals,the impeded crystal growth was divided into three different stages,decided by the hindrance form the other crystal.Further,the groove formed on the crystal surface is directly related to the solute redistribution under the critical condition of boundary layer thickness larger than two crystals distance.The closer distance and smaller crystal size indicate the deeper and larger groove,and the morphology changes from hemispheroid to hemi-ellipsoid with the increased opposite and interacted faces. 展开更多
关键词 SOLIDIFICATION Synchrotron radiography intergrowth behaviour Intermetallic compounds 3-D morphology
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SiO_2 AS HETEROGENEOUS NUCLEI OF INTERGROWTH EUTECTIC IN MODIFIED AS-CAST MEDIUM MANGANESE STEEL 被引量:1
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作者 JIANG Qichuan YAN Jiulin +3 位作者 GUAN Qingfeng WANG Shoushi RONG Fujie LI Zhang Jilin University of Technology,Changchun,China 130025,China associate professor,Jilin University of Technology,Changchun 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1993年第8期156-160,共5页
By calculation of thermodynamics,analysis of crystal structure and study of TEM and eletron probe,it is first discovered that SiO2 can be acted as one of the heterogeneous nu- clei for lamellar intergorowth eutectic(a... By calculation of thermodynamics,analysis of crystal structure and study of TEM and eletron probe,it is first discovered that SiO2 can be acted as one of the heterogeneous nu- clei for lamellar intergorowth eutectic(austenite and cementite)crystallizing in modified as-cast medium manganese steel. 展开更多
关键词 SiO_2 heterogeneous necleus intergrowth eutectic medium manganese steel
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Syntactic Intergrowth Structure in the Calcium-Rare Earth Fluorocarbonate Minerals
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作者 吴秀玲 孟大维 +4 位作者 杨光明 潘兆橹 李斗星 戴吉岩 胡魁毅 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第3期39-44,共6页
The microstructural characteristics of syntactic polycrystal in the calcium rare earth fluorocarbonate minerals from Southwest China have been studied by means of selected area electron diffraction and high resolutio... The microstructural characteristics of syntactic polycrystal in the calcium rare earth fluorocarbonate minerals from Southwest China have been studied by means of selected area electron diffraction and high resolution electron microscopy(HREM). The complication of the heterogeneous fabric of the minerals have been revealed by HREM. The results show that the crystal structure of the minerals was formed by a disorder stacking of the unit layers of bast naesite and synchisite in the calcium rare earth fluorocarbonate minerals along c direction. The stacking fault and other crystal defects in the syntactic polycrystal have been discussed. 展开更多
关键词 Rare earths Calcium rare earth fluorocarbonate mineral Syntactic intergrowth High resolution electron microscopy
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Nano-scale compositional oscillation and phase intergrowth in Cu_(2)S_(0.5)Se_(0.5) and their role in thermal transport
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作者 Yuyu Wei Ping Lu +4 位作者 Chenxi Zhu Kunpeng Zhao Xun Shi Lidong Chen Fangfang Xu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第20期222-229,共8页
Solid solution alloying is a promising strategy to establish high performance thermoelectrics.By alloying different elements,phase structures and phase compositions may vary accompanied by appearance of variety of int... Solid solution alloying is a promising strategy to establish high performance thermoelectrics.By alloying different elements,phase structures and phase compositions may vary accompanied by appearance of variety of interesting microstructures including mass fluctuation,lattice strain,nano-scale defects and spinodal decomposition,all of which may greatly influence the electrical and specifically the thermal transport of the material.In the present study,atomic structures of Cu_(2)S_(0.5)Se_(0.5) solid solution have been examined by using atom-resolved electron microscopy in order to investigate the structure-correlated physical insights for the abnormal thermal transport in this solid solution.Then the exceptional intergrowth nanostructures were observed.The solid solution consists of two high symmetrical phases,i.e.the hexagonal and cubic phase,which alternately intergrow to form highly oriented ultra-thin lamellae of nano or even,unit cell scales.The compositional oscillation in Se/S atomic ratio during alloying is responsible for the phase stability and intergrowth nanostructures.The unique binary phase intergrowth nanostructures make great contribution to the ultra-low lattice thermal conductivity comparable to glass and extremely short phonon mean free path of only 1.04Å,peculiar continuous hexagonal-to-cubic structural transformation without a critical transition temperature and its corresponding abnormal changes of thermal characters with temperatures.The present study further evokes the unlimited possibilities and potentials for tailoring nanostructures by alloying for improved thermoelectric performance. 展开更多
关键词 THERMOELECTRIC Solid solution intergrowth nanostructures Compositional oscillation Structural transformation Thermal transport
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High Yield and Efficient Cultivation Techniques of Rice under Rice- fish Intergrowth Model in Chengdu
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作者 Liangyu LI Shun HE +6 位作者 Hong TANG Xia CHEN Ma YANG Xiaoli ZHANG Jian CHEN Jiaxing LIU WenyanWEI 《Asian Agricultural Research》 2018年第3期76-77,共2页
The integrated planting and breeding of paddy fields is a kind of eco-planting and breeding mode which makes rice and aquatic animals benefit from each other,greatly reducing the harm of rice pests and diseases,using ... The integrated planting and breeding of paddy fields is a kind of eco-planting and breeding mode which makes rice and aquatic animals benefit from each other,greatly reducing the harm of rice pests and diseases,using less or even no fertilizers or pesticides,greatly reducing the agricultural non-point source pollution,thus achieving the " multiple use of water,multiple harvests in one field,grain and fishing winwin,ecological and high efficient use. " In this paper,the high yield and efficient cultivation techniques of rice under the rice-fish intergrowth model in Chengdu was introduced from the aspects of selecting good paddy fields for fishing,using appropriate rice varieties,soaking disinfection,timely sowing and nurturing strong seedlings,reasonable close planting,reasonable fertilization,scientific water management,scientific pest control and rice harvests. 展开更多
关键词 Rice-fish intergrowth model RICE High yield and high efficiency cultivation techniques Chengdu area
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Chalcopyrite Intergrowths in Sphalerite in the Meixian Lead-Zinc Deposit, Fujian Province and Their Metallogenic Significance 被引量:7
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作者 顾连兴 周兵 张文兰 《Chinese Journal Of Geochemistry》 EI CAS 1998年第4期311-319,共9页
Ore textures and electron microprobe analyses show that in addition to highly scattered blebs in sphalerite grains, intergrown chalcopyrite also occurs as reds, myrrmekites andlamellae aligned along cleavages and twin... Ore textures and electron microprobe analyses show that in addition to highly scattered blebs in sphalerite grains, intergrown chalcopyrite also occurs as reds, myrrmekites andlamellae aligned along cleavages and twin boundaries of the host sphalerite. The majority of theintergrowths could have been formed by replacement of sphalerite by chalcopyrite, albeit part ofthem may have resulted from exsolution. Not only copper, but also iron were introduced intothe sphalerite by replacive fluids.While the front of the replacing fluid was moving forward through a sulphide orebody, Znand Pb were dissolved and Cu was precipitated, resulting in zonal refining of the sulphide ores.The remobilized zinc and lead were precipitated at favourable sites with changed physiccrchemical conditions. This is a Possible mechanism for the formation of copper-poor zinc and lead oresabove or lateral to the copper orebodies in some of the massive sulphide deceits reworked andoverprinted by late-stage granites and their hydrothermal fluids. 展开更多
关键词 闪锌矿 黄铜矿 硫化物矿床 共生矿床 福建 锌矿床 找矿标志
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湘东北连云山地区上石锂辉石伟晶岩型矿床的成矿机制——来自全岩和锂辉石地球化学特征
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作者 黄明 刘磊 +4 位作者 刘恒 张云飞 文志林 黄宝亮 周炜鉴 《地质论评》 北大核心 2026年第1期124-146,共23页
已发现的上石锂辉石伟晶岩矿床成矿物质来源及锂富集过程等成矿机制仍需进一步研究。锂辉石伟晶岩脉绝大多数侵入到二云母片岩地层中,锂辉石伟晶岩脉可能与邻近的白沙窝二云母二长花岗岩体存在成因联系。白沙窝二云母二长花岗岩中SiO_(2... 已发现的上石锂辉石伟晶岩矿床成矿物质来源及锂富集过程等成矿机制仍需进一步研究。锂辉石伟晶岩脉绝大多数侵入到二云母片岩地层中,锂辉石伟晶岩脉可能与邻近的白沙窝二云母二长花岗岩体存在成因联系。白沙窝二云母二长花岗岩中SiO_(2)、K_(2)O、Al_(2)O_(3)含量较高,A/CNK值为1.20~1.32,较低的Zr/Hf值(<25)与Nb/Ta值(<5),说明为过铝质类岩石,具有S型花岗岩和高分异的特征。锂辉石伟晶岩结晶分异程度更高,可能形成于岩浆结晶分异末期,岩浆中锂含量能够高度富集达到锂辉石饱和结晶浓度。白沙窝二云母二长花岗岩较低的ε_(Nd)(t)值(-3.87~-8.80)以及Nd二阶段模式年龄(1.41~1.93 Ga),说明可能源自华南元古宙地壳物质的重熔。白沙窝花岗岩较高的FeO^(T)/(FeO^(T)+MgO)值(0.85~0.87),明显的Ba—Sr—Eu负异常和较低Cr、Co的含量,说明其形成于贫水还原环境。白沙窝岩体由富长英质黏土(泥质)的华南元古宙地壳在贫水还原环境下部分熔融形成,其初始岩浆中具有更高的锂含量。富长英质黏土的花岗岩源区部分熔融形成富矿岩浆,富矿岩浆高度演化导致锂高度富集达到锂辉石结晶浓度,这两种因素的叠加促使了上石锂辉石伟晶岩矿床的形成。岩相学结构显示在岩浆体系中较早结晶的锂辉石颗粒边缘不均匀分布锂辉石—石英共生结构(Spodumene—quartz intergrowth,简称SQI结构)。SQI结构可能是透锂长石分解的产物,受成矿环境温压条件改变影响形成。锂辉石中Sn、Ga的含量与Fe、Mn含量具有较强的正相关性,Sn、Ga等稀有金属元素可能通过Fe、Mn类质同像替代Li的过程进入锂辉石。成矿过程中,锂辉石中发生Fe替代Al,Al替代Si—O四面体中Si等现象,促进了矿物结晶生长,有利于稀有金属等成矿元素的富集。 展开更多
关键词 锂辉石伟晶岩型矿床 锂辉石—石英共生结构 Sr—Nd同位素 连云山地区
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Block-layer model for intergrowth structures 被引量:1
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作者 Zhicheng Wang Siqi Wu +1 位作者 Liangwen Ji Guanghan Cao 《Nano Research》 SCIE EI CSCD 2021年第10期3629-3635,共7页
Lattice match and charge transfer between distinct block layers(BLs)play an important role in the formation of an intergrowth structure.Herein we propose a simple BL model addressing the different roles of the lattice... Lattice match and charge transfer between distinct block layers(BLs)play an important role in the formation of an intergrowth structure.Herein we propose a simple BL model addressing the different roles of the lattice match and the charge transfer.Inter-BL charge transfer lowers the internal energy,while lattice match minimizes the elastic energy,both of which together make the intergrowth structure stabilized.The model is able to reproduce the lattice parameters precisely for complex iron-based superconductors with intergrowth structures.The elastic energy and the charge-transfer energy are evaluated with assistance of the first-principles calculations.This work rationalizes the basic principles of BL design for intergrowth structures,which can be utilized not only for finding new superconducting materials but also for investigating other layered materials with various functionalities. 展开更多
关键词 structural design intergrowth structures lattice match interlayer charge transfer iron-based superconductors
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TOPOTACTIC INTERGROWTH OF LONGQUAN MAGNESIOAMPHIBOLE
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作者 薛纪越 马军 张富生 《Chinese Science Bulletin》 SCIE EI CAS 1991年第18期1553-1556,共4页
Ⅰ. OCCURRENCE AND GENERAL FEATURES OF LONGQUAN MAGNESIOAMPHIBOLEThe magnesioamphibole studied in this note was sampled from peridotite block in Longquan tectonic melange zone of Zhejiang Province, China. It appears i... Ⅰ. OCCURRENCE AND GENERAL FEATURES OF LONGQUAN MAGNESIOAMPHIBOLEThe magnesioamphibole studied in this note was sampled from peridotite block in Longquan tectonic melange zone of Zhejiang Province, China. It appears in bunchy or fibrous aggregates around the block. The length of the crystal ranges from several mm to about 1 cm. It presents inchned extinction with cANg= 10°—13°under crossed polars. According to the observation of thin sections, it is known that olivine, tale and serpentine 展开更多
关键词 topotnctic intergrowth magnesiocummingtonite anthophyllite.
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四川雷波某低品位磷矿工艺矿物学研究
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作者 张巍 唐彬彬 +3 位作者 冯振华 李成 蒋文杰 唐飏 《现代矿业》 2026年第1期154-159,共6页
为了高效利用四川雷波某低品位难选磷矿石,采用化学分析、岩矿鉴定、X射线衍射仪(XRD)、矿物自动分析仪(MLA)等分析手段对该磷矿石的化学成分、矿物组成、矿物嵌布特征及粒度、单体解离与连生特性进行了系统的研究。研究结果表明:该磷... 为了高效利用四川雷波某低品位难选磷矿石,采用化学分析、岩矿鉴定、X射线衍射仪(XRD)、矿物自动分析仪(MLA)等分析手段对该磷矿石的化学成分、矿物组成、矿物嵌布特征及粒度、单体解离与连生特性进行了系统的研究。研究结果表明:该磷矿属于低品位高硅型镁硅质磷矿石,主要矿物为磷灰石(胶磷矿),其次为石英和白云石,含有少量方解石、白云母、黄铁矿等,磷灰石、白云石嵌布粒度较细,同时和石英密切连生;工艺矿物学和探索试验结果表明,可采用增加磨矿细度提高矿物解离度,再通过X射线光选预先抛尾工艺,并联合浮选工艺脱镁(白云石)降硅(石英),可获得高品质的磷精矿产品。 展开更多
关键词 镁硅质磷矿 胶磷矿 工艺矿物学 单体解离度 连生
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INTERGROWTH-21^(st)标准结合主动脉峡部血流参数评价晚发型胎儿生长的影响
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作者 许传塍 肖雪花 +1 位作者 杨海云 叶萍 《中华实验外科杂志》 CAS 北大核心 2023年第11期2374-2377,共4页
目的:探讨INTERGROWTH-21^(st)标准结合主动脉峡部血流参数评价晚发型胎儿生长受限(FGR)的意义。方法:选取九江学院附属医院2020年1月至2023年1月在进行常规产前检查并入院分娩的100例孕妇为研究的对象,根据孕产妇的分娩结局分为正常胎... 目的:探讨INTERGROWTH-21^(st)标准结合主动脉峡部血流参数评价晚发型胎儿生长受限(FGR)的意义。方法:选取九江学院附属医院2020年1月至2023年1月在进行常规产前检查并入院分娩的100例孕妇为研究的对象,根据孕产妇的分娩结局分为正常胎儿组(88例)和晚发型胎儿生长受限组(12例),所有孕产妇均行彩色多普勒超声检测胎儿主动脉峡部血流指数(IFI)及峡部收缩指数(ISI),并以超声监测相关参数,包括双顶径(BPD)、头围(HC)、股骨长(FL)、腹围(AC)等;分别以INTERGROWTH-21^(st)公式与INTERGROWTH-21^(st)公式结合主动脉峡部血流参数对胎儿体重进行预测,比较两种方式对FGR的预测准确性。计量资料以均数±标准差(±s)表示,采用t检验,计数资料以率(%)表示.采用χ^(2)检验。结果:本组100例孕妇分娩结局,88例为正常胎儿,12例为FGR。正常组胎儿体质量及新生儿Apgar评分(3.591±0.420,1.643±0.420),晚发组胎儿体质量及新生儿Apgar评分(8.260±1.500,6.760±1.812),两组间差异有统计学意义(χ^(2)=4.561,P<0.05)。正常组胎儿双顶径为(8.320±0.790)cm,头围为(29.460±5.780)cm,股骨长为(70.126±6.831)cm,腹围为(30.641±3.290)cm,晚发组胎儿双顶径[(7.122±0.218)cm],头围[(23.141±2.800)cm],股骨长[(62.430±4.780)cm],腹围[(28.414±2.780)cm]直径均值低于正常组,差异有统计学意义(χ^(2)=18.923,P<0.05)。晚发型FGR组胎儿主动脉峡部舒张期血流消失或反向发生率42.25%(5/12),高于对照组13.40%(1/12),差异有统计学意义(χ^(2)=2.110,P<0.01)。INTERGROWTH-21^(st)标准结合主动脉峡部血流参数对FGR预测的准确性为92.0%(92/100),单纯INTERGROWTH-21^(st)标准对FGR预测的准确性为81.0%(81/100),两者差异有统计学意义(χ^(2)=5.181,P<0.05)。结论:INTERGROWTH-21^(st)标准结合主动脉峡部血流参数评价FGR中的作用显著,有助于评价晚发型胎儿生长受限。 展开更多
关键词 intergrowth-21^(st)标准 主动脉峡部血流 晚发型胎儿宫内生长受限
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Intergrowth texture in Au-Ag-Te minerals from Sandaowanzi gold deposit,Heilongjiang Province:Implications for ore-forming environment 被引量:7
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作者 XU Hong YU YuXing +4 位作者 WU XiangKe YANG LiJun TIAN Zhu GAO Shen WANG QiuShu 《Chinese Science Bulletin》 SCIE CAS 2012年第21期2778-2786,共9页
Sandaowanzi gold deposit,Heilongjiang Province,is the only single telluride type gold deposit so far documented in the world,in which 90% of gold is hosted in gold-silver telluride minerals.Optical microscope observat... Sandaowanzi gold deposit,Heilongjiang Province,is the only single telluride type gold deposit so far documented in the world,in which 90% of gold is hosted in gold-silver telluride minerals.Optical microscope observation,scanning electron microscope,electron probe and X-ray diffraction analysis identified abundant intergrowth textures in the Au-Ag-Te minerals,typified by sylvanite-hosting hessite crystals and hessite-hosting petzite crystals.The intergrown minerals and their chemistry are consistent,and the hosted minerals are mostly worm-like or as oriented stripes,evenly distributed in the hosting minerals,with clear and smooth interfaces.These suggest an exsolution origin for the intergrowth texture.With reference to the phase-transformation temperature derived from synthesis experiments of tellurides,the exsolution texture of Au-Ag-Te minerals implies that the veined tellurides formed at 150-220℃.The early stage disseminated tellurides formed at log f(Te 2) from 13.6 to 7.8,log f(S 2) from 11.7 to 7.6,whereas the late stage veined tellurides formed at log f(Te 2) ranging from 11.2 to 9.7 and log f(S 2) from 16.8 to 12.2. 展开更多
关键词 三道湾子金矿 金银碲化物 矿物共生 黑龙江省 成矿环境 纹理 扫描电子显微镜 X射线衍射分析
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蒙古国某萤石矿石的可选性研究 被引量:1
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作者 王利珍 姜楚灵 +3 位作者 朱家祥 沈力微 王祥 王伟 《金属矿山》 北大核心 2025年第4期103-108,共6页
为了了解蒙古国三大萤石矿CH、BB、NU矿石的可选性,通过化学多元素分析、X射线衍射分析、显微镜鉴定和MLA等方法对这些矿山的代表性矿石进行了工艺矿物学特性研究。结果表明:(1)CH、BB和NU矿样CaF_(2)品位分别为46.73%、48.49%和81.89%... 为了了解蒙古国三大萤石矿CH、BB、NU矿石的可选性,通过化学多元素分析、X射线衍射分析、显微镜鉴定和MLA等方法对这些矿山的代表性矿石进行了工艺矿物学特性研究。结果表明:(1)CH、BB和NU矿样CaF_(2)品位分别为46.73%、48.49%和81.89%,萤石多呈致密团块状产出,粒度一般1.0~2.0 mm,团块中偶或包裹或浸染微细粒石英等脉石矿物,预计适当磨矿可获得有效解离。(2)碎磨至-3 mm的CH、BB和NU矿样中萤石全部回收对应的精矿CaF_(2)品位预计值分别为72.09%、54.70%和89.00%,产率预计值分别为64.82%、88.65%和92.01%,BB和NU矿样在该细度下预选抛尾意义不大;碎磨至-0.15 mm的CH、BB和NU矿样中萤石全部回收对应的精矿CaF_(2)品位预计值分别较-3 mm情况下提高10.20、21.86和8.20个百分点,产率预计值显著下降至50.18%、63.33%和84.25%,抛尾提质效果显著,适当抛出贫连生体能显著提高精矿CaF_(2)品位。(3)CH、BB和NU矿样在磨矿细度为-0.15 mm的情况下,采用1粗4精、精选1尾矿直接抛尾、精选2及后续精选尾矿合并返回流程处理,均可获得CaF_(2)品位97%以上的萤石精矿,探索试验指标与预测指标接近,精矿品质均达到《中华人民共和国黑色冶金行业标准》(YB/T 5217—2019)之酸级萤石一级品质量标准,表明矿样具有较好的可选性。 展开更多
关键词 萤石 工艺矿物学 嵌布特征 单体解离度 连生体 浮选抛尾
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意境相生:杭州亚运会中宋韵色彩的“活态化”叙事设计
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作者 成朝晖 《色彩》 2025年第9期1-6,共6页
本文聚焦于宋韵色彩的当代转译与实践:溯源其美学基因与意境内核,从宋代色彩的美学维度切入,分析宋代艺术典型载体中的色彩叙事逻辑,为当代设计转译奠定理论基础;以杭州亚运会为案例,探讨宋韵色彩“活态化”转译的路径,阐释“活态化”... 本文聚焦于宋韵色彩的当代转译与实践:溯源其美学基因与意境内核,从宋代色彩的美学维度切入,分析宋代艺术典型载体中的色彩叙事逻辑,为当代设计转译奠定理论基础;以杭州亚运会为案例,探讨宋韵色彩“活态化”转译的路径,阐释“活态化”叙事设计的内涵,并解析从宋韵“诗意”到“画意”的转译方法;进而从多场景叙事的层次建构与跨媒介转译的实践探索入手,深入探究宋韵色彩在杭州亚运会“活态化”叙事设计中的“意境相生”表达方法,为宋韵文化的创造性转化提供理论支撑与实践借鉴。 展开更多
关键词 意境相生 杭州亚运会 宋韵色彩 活态化 叙事设计
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难选铁尾矿中连生体的离心分选及铁回收机制 被引量:1
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作者 邱国强 叶文盛 +2 位作者 宁寻安 张鼎元 梁永钊 《环境工程学报》 北大核心 2025年第9期2237-2246,共10页
铁矿石的Fe-Si连生体是制约铁品位提高的重要因素。磁化焙烧可以从难选铁尾矿中进行高效铁回收,但连生体和铁品位、铁回收率的关联机制尚不清晰。本研究以广东大宝山难选铁尾矿为研究对象,系统探讨了连生体的离心分选与铁回收机制。通... 铁矿石的Fe-Si连生体是制约铁品位提高的重要因素。磁化焙烧可以从难选铁尾矿中进行高效铁回收,但连生体和铁品位、铁回收率的关联机制尚不清晰。本研究以广东大宝山难选铁尾矿为研究对象,系统探讨了连生体的离心分选与铁回收机制。通过离心实现不同连生度铁尾矿的分离,验证了铁尾矿连生度与密度的线性关系。采用印染污泥-磁化焙烧工艺,结合XRD和SEM揭示了焙烧温度和时间对连生体变化与铁精矿品位的作用机制。研究结果表明,焙烧条件为750℃和50 min时,可有效降低铁尾矿连生度至60.74%。铁尾矿初始连生度从83.48%减少至61.49%时,磁化焙烧及磁分选后的铁精矿铁品位从60.32%增大至61.99%,铁回收率从93.15%增大至94.52%,其中连生度对铁精矿品位有显著影响。本研究结果为难选铁尾矿的高效资源化及铁精矿提质提供了重要的理论指导。 展开更多
关键词 磁化焙烧 铁尾矿 离心 连生体 铁回收
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