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Phosphoglyceride crystal deposition disease requiring differential diagnosis from malignant tumors and confirmed by Raman spectroscopy: A case report
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作者 Yu Ohkura Hironori Uruga +5 位作者 Masato Shiiba Shinji Ito Hayato Shimoyama Makiko Ishihara Masaki Ueno Harushi Udagawa 《World Journal of Clinical Cases》 SCIE 2022年第23期8304-8311,共8页
BACKGROUND Phosphoglyceride crystal deposition disease(PCDD)is a rare acquired disease in which phospholipid crystals deposit in bone and soft tissue long after surgery,trauma,or repeated injections.CASE SUMMARY A 60-... BACKGROUND Phosphoglyceride crystal deposition disease(PCDD)is a rare acquired disease in which phospholipid crystals deposit in bone and soft tissue long after surgery,trauma,or repeated injections.CASE SUMMARY A 60-year-old-woman was referred to our department because of multiple abdominal masses after open splenectomy for idiopathic thrombocytopenic purpura 29 years earlier.All the masses showed marked fluorodeoxyglucose(FDG)uptake on ^(18)F-fluorodeoxyglucose positron emission tomography(^(18)F-FDGPET)and were strongly suspected to be malignant tumors.Surgical biopsies were performed,and the abdominal masses were found to be aligned vertically,three in a row,along the tissue layers cut in the patient’s previous surgery.Pathological finding of the specimens showed foreign body granuloma consisting of histiocytes and multinucleated giant cells accumulating around needle-like crystals.The crystals were confirmed as phosphoglyceride by Raman spectroscopy,and PCDD was diagnosed.To our knowledge,this is the first report of PCDD diagnosed by Raman spectroscopy.CONCLUSION We made a definitive diagnosis of PCDD in a patient with multiple tumors showing marked FDG uptake on ^(18)F-FDG-PET by incisional biopsy and composition analysis using Raman spectroscopy,a method that has not previously been reported for the diagnosis of PCDD. 展开更多
关键词 Phosphoglyceride crystal deposition disease Raman spectroscopy Positron emission tomography Foreign body granuloma with crystal deposition Surgical scar Case report
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A MODELING STUDY OF PARAMETERIZATION SCHEMES FOR DEPOSITIONAL GROWTH OF ICE CRYSTAL:FOUR RAINFALL CASES OVER TROPICS AND MIDLATITUDES
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作者 辛进 李小凡 《Journal of Tropical Meteorology》 SCIE 2017年第3期259-268,共10页
Depositional growth of ice crystal is one of the major processes for development of precipitation systems and can be represented by depositional growth of cloud ice from cloud water(P_(IDW)) and depositional growth of... Depositional growth of ice crystal is one of the major processes for development of precipitation systems and can be represented by depositional growth of cloud ice from cloud water(P_(IDW)) and depositional growth of snow from cloud ice(P_(SFI)) in cloud-resolving model. Four parameterization schemes are analyzed in the cloud-resolving model simulations of four rainfall cases over the tropics and midlatitudes. The comparison of time and model domain mean data shows that Shen's scheme produces the closest rainfall simulation to the observation. Compared to Zeng's scheme,Shen's scheme improves the mean rain-rate simulation significantly through the dramatic decrease in depositional growth of cloud ice from cloud water. Compared to other schemes, Shen's scheme produces the better rainfall simulation via the reduction in the mean rain rate associated with the enhanced gain of cloud water and ice. 展开更多
关键词 depositional growth of ice crystal rainfall simulation rain rate cloud-resolving-model simulation
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Effect of Particle Inhomogeneity on Band-gap of Silica Colloidal Crystals in Vertical Deposition Method
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作者 周倩 董鹏 《过程工程学报》 CAS CSCD 北大核心 2009年第S2期127-130,共4页
The effect of inhomogeneity of particles on the band-gap of silica colloidal crystals(SCCs) fabricated by vertical deposition method was studied.The optical properties of the crystals were examined.The SEM images and ... The effect of inhomogeneity of particles on the band-gap of silica colloidal crystals(SCCs) fabricated by vertical deposition method was studied.The optical properties of the crystals were examined.The SEM images and transmission spectrum of the crystals showed that the inhomogeneity of particles not only affected the ordering,but also their mid-gap position.When the volume ratio of S particles(VS) to L particles(VL) in suspension was 1:1,the band-gap of silica colloidal crystals changed with the growth of particles.When the ratio was 2:1,the quality of SCCs on substrate was obviously improved simultaneously with the number decreasing of L particles.Especially,the quality of SCCs at the bottom of substrate was the best and its mid-gap(634 nm) was very close to that of theoretic value of S particles(636 nm).When the ratio was 3:1,the effect of L particles became smaller with the number decreasing of L particles in suspension.The mid-gap position(638 nm) of whole SCCs on substrate were all close to that of theoretic value of S particles(636 nm). 展开更多
关键词 COLLOIDAL SILICA particles COLLOIDAL crystalS INHOMOGENEITY VERTICAL depositION
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In situ Investigation on Layer-by-Layer Deposition of Polyelectrolytes by Quartz Crystal Microbalance
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作者 Yun-fengYan Guang-ming Liu Ye-cang Tang Guang-zhao Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第3期291-294,共4页
layer-by-layer 免职上的盐集中的效果(钠 4 苯乙烯 sulfonate )(PSSS ) poly, /poly (vinylbenzyl trimethylammonium 氯化物)(PVTC ) 被石英水晶微量天秤的使用与驱散(QCM-D ) 调查。在频率和驱散的变化证明 NaCl 的增加导致多层的 P... layer-by-layer 免职上的盐集中的效果(钠 4 苯乙烯 sulfonate )(PSSS ) poly, /poly (vinylbenzyl trimethylammonium 氯化物)(PVTC ) 被石英水晶微量天秤的使用与驱散(QCM-D ) 调查。在频率和驱散的变化证明 NaCl 的增加导致多层的 PSSS/PVTC 的厚度增加。PSSS/PVTC 的免职被表面费用过度补偿水平在更低的盐集中统治。然而,它被聚合电解质的互相贯通主要在更高的盐集中决定,在驱散变化的摆动思考了。 展开更多
关键词 聚电解质 层叠层组装 石英晶体微天平 渗透程度
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Crystallization of NiTi shape memory alloy sputtering-deposition film
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作者 QIU Ping shan(邱平善) SONG Run bin(宋润滨) +3 位作者 HUANG Wei xin(黄渭馨) LI Yun xi(李运稀) WANG Gui song(王桂松) YU Wei dong(于伟东) 《中国有色金属学会会刊:英文版》 CSCD 2000年第3期320-323,共4页
The crystallization of NiTi shape memory alloy sputter deposition film in the course of sputtering deposition and that after heat treated were studied. The relationship between the process factors, such as substrate t... The crystallization of NiTi shape memory alloy sputter deposition film in the course of sputtering deposition and that after heat treated were studied. The relationship between the process factors, such as substrate type, temperature, as well as the crystallization when heat treated after plating was investigated. The results show that a new phase precipitates during heat treatment after sputtering deposition and the degree of crystallization among different layers and the stress in grains are obviously different. 展开更多
关键词 SPUTTERING depositION films crystalLIZATION SHAPE MEMORY ALLOYS
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Growth Pattern and Its Indication of Spheroidal Nano-Micro Crystal Aggregates of Pyrite in the Baiyunpu Pb-Zn Polymetallic Deposit, Central Hunan 被引量:2
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作者 GAO Shang HUANG Fei +6 位作者 GU Xiangping LI Xiangyou MENG Lin LIU Rui SUN Li GAO Wenyuan YU Huantao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1770-1783,共14页
The Baiyunpu deposit lies in the southwest plunging Dachengshan anticline in central Hunan, which is a large Pb-Zn polymetallic deposit. The orebodies were surrounded by the Qiziqiao Formation limestone in the Middle ... The Baiyunpu deposit lies in the southwest plunging Dachengshan anticline in central Hunan, which is a large Pb-Zn polymetallic deposit. The orebodies were surrounded by the Qiziqiao Formation limestone in the Middle Devonian, and its geological occurrence is consistent with the wall rocks. A large number of spheroidal pyrite aggregates are found unevenly distributed in the ores. The spheroidal aggregates are made up of kernels and concentric rings. The kernels are composed of approximately epigranular pyrite nanocrystals, while the rings are composed of accumulated pyrite microcrystals growing along the radial direction. The spheroidal pyrite aggregate and its outer zones can be divided into five areas(A–E). The results of electron probe micro analysis(EPMA) show that from the zone A1 to B, Co/Ni 〈1, the sum of Co and Ni is 0.08%–0.26%, S/Fe increases from 2.06 to 2.15. While from the zone C to E, Ni cannot be detected and S/Fe decreases from 2.22 to 2.08. Powder X-ray diffraction(XRD) analysis in the micro zone shows obvious crystalline characteristics in the aggregates. Moving from the inside outwards, the maximum diffraction peak intensity of the(111) and(220) crystal planes of pyrite increases, and the crystallinity improves. The degree of change in the(111) plane is the most prominent. Considering the theory of crystal growth along with the geologic features of the depositional environment where the spheroidal pyrite aggregates developed, we confirm that the spheroidal aggregates are the result of nano-micro crystalline gathering and growth occurring by the following sequence of processes:nano-crystalline nucleation and growth, gathering into a ball, oriented growth of microcrystals, continuous accumulation, and adjustment of grain boundaries. The formation of the spheroidal pyrite aggregates in the late Qiziqiao Formation of the Middle Devonian occurred in a neutral to weak alkaline and reductive sedimentary environment in the normal oxygen-rich shallowwater carbonate platform edge. The variations in the S/Fe ratio and crystallisation characteristics indicate that during pyrite crystal growth, the sulphur fugacity was high locally and rose constantly, the degree of supersaturation decreased locally and the growth environment was stable relatively. 展开更多
关键词 Baiyunpu Pb-Zn polymetallic deposit PYRITE nano-micro crystal spheroidal aggregates growth pattern indication significance
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High-quality SiO_2 Colloidal Crystal Fabricated by Controllable Vertical Deposition Method
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作者 CAI Xiao-mei CHEN Fu-yi JIE Wan-qi 《Semiconductor Photonics and Technology》 CAS 2006年第2期95-99,共5页
Monodispersed silica microspheres with diameter of 353nm were assembled into photonic crystal in ethanol colloidal suspensions of varied silica volume fraction at different temperature and humidity by means of contr... Monodispersed silica microspheres with diameter of 353nm were assembled into photonic crystal in ethanol colloidal suspensions of varied silica volume fraction at different temperature and humidity by means of controllable vertical deposition method. The surface morphology and optical properties were studied by SEM and UV-Vis-NIR. It was found that the high-quality silica colloidal photonic crystals were obtained from ethanol solutions with environment temperature between 45℃ and 55℃, humidity between 66% and 76%, the volume fraction of microspheres is between 0.8% and 1.5%. The ordered close-packed photonic crystal fabricated by controllable vertical deposition method had the two photonic bandgaps in the visible light band and near infrared band. 展开更多
关键词 光子晶体 二氧化硅晶体 沉积作用 光子能隙带
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Quartz Crystal Microbalances for Evaluating Gas Motion Differences between Dichlorosilane and Trichlorosilane in Ambient Hydrogen in a Slim Vertical Cold Wall Chemical Vapor Deposition Reactor 被引量:1
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作者 Mana Otani Toshinori Takahashi +3 位作者 Hitoshi Habuka Yuuki Ishida Shin-Ichi Ikeda Shiro Hara 《Advances in Chemical Engineering and Science》 2020年第3期190-200,共11页
A dichlorosilane gas and a trichlorosilane gas in ambient hydrogen were evaluated to show their different gas flow motions in a slim vertical cold wall chemical vapor deposition reactor for the Minimal Fab system. Thi... A dichlorosilane gas and a trichlorosilane gas in ambient hydrogen were evaluated to show their different gas flow motions in a slim vertical cold wall chemical vapor deposition reactor for the Minimal Fab system. This evaluation was performed for improving and controlling the film qualities and the productivities, using two quartz crystal microbalances (QCM) installed at the </span><span style="font-family:Verdana;">inlet and exhaust of the chamber by taking into account that the QCM frequency corresponds to the real time changes in the gas properties.</span><span style="font-family:Verdana;"> Typically, the time period approaching from the inlet to the exhaust was shorter for the trichlorosilane gas than that for the dichlorosilane gas. The trichlorosilane gas was shown to move like plug flow, while the dichlorosilane gas seemed to be well mixed in the entire chamber. 展开更多
关键词 Minimal Fab Chemical Vapor deposition Reactor Quartz crystal Microbalance Silicon Epitaxial Growth TRICHLOROSILANE DICHLOROSILANE
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Influence of Deposition Conditions on the Crystal Structure of MoS_2 Coating
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作者 Jihui WANG Yang XIA +3 位作者 E. Wieers L.M.Stals X.Zhang J.P.Celis 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第3期324-328,共5页
MoS2 coatings were prepared using an unbalanced bipolar pulsed DC (direct current) magnetron sputtering apparatus under different targets, cathode current densities, power modes and bias voltages. The morphology, st... MoS2 coatings were prepared using an unbalanced bipolar pulsed DC (direct current) magnetron sputtering apparatus under different targets, cathode current densities, power modes and bias voltages. The morphology, structure and growth characteristics of MoS2 coatings were observed and identified respectively by scanning electron microscopy, X-ray diffractometry and mass spectrometry. The results show that MoS2 coatings evolve with the (002) basal plane parallel to the surface by using cold pressed target with lower density, lower cathodic current density, bipolar pulse DC power and minus bias voltage, whereas the coatings deposited under hot pressed target, higher cathodic current density, simple DC power and positive bias voltage have the (002) basal plane perpendicular to the surface. The influence of deposition conditions on the crystal structure of MoS2 coating is implemented by altering its growth rate and the energy of sputtering-deposition particles. 展开更多
关键词 deposition condition Molybdenum disulfide COATING crystal structure
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High-crystalline GaSb epitaxial films grown on GaAs(001) substrates by low-pressure metal–organic chemical vapor deposition
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作者 王连锴 刘仁俊 +4 位作者 吕游 杨皓宇 李国兴 张源涛 张宝林 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期114-118,共5页
Orthogonal experiments of Ga Sb films growth on Ga As(001) substrates have been designed and performed by using a low-pressure metal–organic chemical vapor deposition(LP-MOCVD) system. The crystallinities and mic... Orthogonal experiments of Ga Sb films growth on Ga As(001) substrates have been designed and performed by using a low-pressure metal–organic chemical vapor deposition(LP-MOCVD) system. The crystallinities and microstructures of the produced films were comparatively analyzed to achieve the optimum growth parameters. It was demonstrated that the optimized Ga Sb thin film has a narrow full width at half maximum(358 arc sec) of the(004) ω-rocking curve, and a smooth surface with a low root-mean-square roughness of about 6 nm, which is typical in the case of the heteroepitaxial single-crystal films. In addition, we studied the effects of layer thickness of Ga Sb thin film on the density of dislocations by Raman spectra. It is believed that our research can provide valuable information for the fabrication of high-crystalline Ga Sb films and can promote the integration probability of mid-infrared devices fabricated on mainstream performance electronic devices. 展开更多
关键词 crystal growth metal–organic chemical vapor deposition thin films
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<i>In-Situ</i>Monitoring of Chemical Vapor Deposition from Trichlorosilane Gas and Monomethylsilane Gas Using Langasite Crystal Microbalance
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作者 Hitoshi Habuka Yurie Tanaka 《Journal of Surface Engineered Materials and Advanced Technology》 2013年第1期61-66,共6页
Using the langasite crystal microbalance (LCM), the trends in film thickness produced by means of the chemical vapor deposition using trichlorosilane gas, monomethylsilane gas and their mixed gas were observed at 600?... Using the langasite crystal microbalance (LCM), the trends in film thickness produced by means of the chemical vapor deposition using trichlorosilane gas, monomethylsilane gas and their mixed gas were observed at 600?C and evaluated by comparison with the information from a transmission electron microscope (TEM). The crystalline silicon film thickness from trichlorosilane gas was comparable to that of an amorphous silicon carbide film from monomethylsilane gas. The film obtained from the gas mixture was amorphous and was the thinnest in this study. Because the thickness trend obtained by the LCM agreed with that by the TEM, the LCM is shown to be a convenient evaluation tool for the behavior of various film deposition. 展开更多
关键词 Chemical Vapor deposition IN-SITU Measurement LANGASITE crystal MICROBALANCE
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Structure of Cu-Phthalocyanine Vacuum Deposited on Inclined Glass Substrates
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作者 Masato Ohmukai Yasutaka Kato 《World Journal of Engineering and Technology》 2023年第4期770-774,共5页
Cu-phthalocyanine is widely studied as a hole-transport layer in organic electronic devices. Since Cu-phthalocyanine is a molecular solid, the crystal structure depends on a circumstance to a great extent. Vacuum depo... Cu-phthalocyanine is widely studied as a hole-transport layer in organic electronic devices. Since Cu-phthalocyanine is a molecular solid, the crystal structure depends on a circumstance to a great extent. Vacuum deposited layers were known to consist of two consecutive layers. In this article, Cu-phthalocyanine was deposited on the glass substrate inclined at several angles. The thickness of the first layer was found to be dependent on the substrate angle. 展开更多
关键词 Cu-Phthalocyanine Vacuum deposition crystal Structure Inclined Substrate
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热丝化学气相沉积法制备单晶金刚石的试验研究
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作者 张川 刘栋栋 +1 位作者 陆明 孙方宏 《金刚石与磨料磨具工程》 CAS 北大核心 2024年第3期279-285,F0003,共8页
热丝化学气相沉积法沉积区域可达12英寸(30.48 cm),其具备大批量生产单晶金刚石的潜力。采用尺寸为3 mm×3 mm×1 mm,(100)取向的单晶金刚石为基体,利用热丝化学气相沉积法以甲烷和氢气为前驱体,同时通入少量氮气进行同质外延... 热丝化学气相沉积法沉积区域可达12英寸(30.48 cm),其具备大批量生产单晶金刚石的潜力。采用尺寸为3 mm×3 mm×1 mm,(100)取向的单晶金刚石为基体,利用热丝化学气相沉积法以甲烷和氢气为前驱体,同时通入少量氮气进行同质外延生长。结果表明,在热丝温度为2200℃、碳源浓度为4%、腔体气压为4 kPa的条件下,单晶金刚石以3.41μm/h的速度生长,表面无多晶、破口、孔洞等缺陷;外延层X射线衍射光谱在(400)面处峰值的半高宽为0.11°,低于基体的半高宽0.16°,证明外延层具有较高的晶体质量;氮气的引入可以提升单晶金刚石的生长速度,同时降低外延层的晶体质量,较高的氮气浓度还会使得单晶金刚石的生长模式转为岛状生长。 展开更多
关键词 热丝化学气相沉积法 单晶金刚石 工艺参数优化 氮气掺杂
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LA-ICP-MS zircon U-Pb age of rhyolitic lithic-crystal tuffs in Erdaohezi lead-zinc deposit,Inner Mongolia 被引量:2
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作者 YAN Jia SUN Jinggui +1 位作者 ZHAO Shifeng MING Zhu 《Global Geology》 2015年第4期213-220,共8页
Erdaohezi lead-zinc deposit belongs to the Derbugan metallogenic belt lying on the northwestern Hailaer-Genhe Mesozoic volcanic basin,located on the western slope of the Da Hinggan Mountains. The deposit is considered... Erdaohezi lead-zinc deposit belongs to the Derbugan metallogenic belt lying on the northwestern Hailaer-Genhe Mesozoic volcanic basin,located on the western slope of the Da Hinggan Mountains. The deposit is considered as one of the hypabyssal low-temprature hydrothermal lead-zinc deposits associated with volcanism. In order to lay the foundation on studying its diagenesis and mineralization ages,the detailed studies were carried out by dating the host rocks( i. e. rhyolitic lithic-crystal tuffs) using zircon LA-ICP-MS U-Pb method.The dating results show three groups of ages. The first group is the captured zircons( the weighted mean ^(206)Pb /^(238) U age as 175. 6 ± 2. 3 Ma,MSWD = 0. 70,n = 3). The second group can be regarded as the rockforming age( the weighted mean ^(206)Pb /^(238) U age as 165. 3 ± 1. 9 Ma,MSWD = 2. 40,n = 14). The third group should represent the late stage of the magmatic evolution( the weighted mean ^(206)Pb /^(238) U age as 161. 0 ± 3. 1Ma,MSWD = 0. 86,n = 4). According to the ages and the crystal form or CL image characteristics of zircons,it is determined that the diagenesis occurred in the late Middle Jurassic. Based on the regional geology and geochronological research,the acidic pyroclastic rocks are space accompaniment and time connection with the Tamulangou Formation intermediate-mafic volcanic rocks. Both of them constitute the host rocks of the deposit together. The rock combination also provides favorable conditions for large-scale silver,lead and zinc mineralization in this area. 展开更多
关键词 锆石U-PB年龄 LA-ICP-MS 铅锌矿床 流纹质 晶簇 岩屑 内蒙古 得尔布干成矿带
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三磷酸腺苷结合盒转运蛋白G2与痛风病关联的病理机制研究进展
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作者 韩宇 黄锦坚 +2 位作者 林志健 张冰 王雨 《世界中医药》 CAS 北大核心 2024年第3期437-443,共7页
痛风病是指与高尿酸血症、尿酸盐沉积(关节、肾脏)等尿酸代谢紊乱密切相关的进展性代谢疾病,根据其病理进展特点和临床表现,其病程可分为高尿酸血症阶段、尿酸盐沉积阶段、痛风性炎症阶段。三磷酸腺苷结合盒转运蛋白G2(ABCG2)是高通量... 痛风病是指与高尿酸血症、尿酸盐沉积(关节、肾脏)等尿酸代谢紊乱密切相关的进展性代谢疾病,根据其病理进展特点和临床表现,其病程可分为高尿酸血症阶段、尿酸盐沉积阶段、痛风性炎症阶段。三磷酸腺苷结合盒转运蛋白G2(ABCG2)是高通量的尿酸转运体,既参与了机体尿酸外排的肠-肾途径,又与痛风性炎症密切相关。通过切入ABCG2,对痛风病病理机制研究进展进行综述,以期为临床痛风病的深入研究及防治提供新的见解。 展开更多
关键词 三磷酸腺苷结合盒转运蛋白G2 痛风病 高尿酸血症 痛风性关节炎 尿酸盐沉积 尿酸代谢 病理机制 研究进展
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滇中禄劝九龙巨晶方解石矿床地质特征与成因
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作者 周红琳 魏爱英 +1 位作者 张佳慧 薛传东 《地质找矿论丛》 CAS 2024年第1期80-86,共7页
滇中禄劝九龙方解石矿床是云南省规模最大的方解石矿床,以产出巨晶方解石矿为特点。本文在系统的野外地质调查和勘查评价基础上,分析了九龙巨晶方解石矿床的基本地质特征和控矿因素,探讨其成因。结果表明,区内方解石矿体呈层状、似层状... 滇中禄劝九龙方解石矿床是云南省规模最大的方解石矿床,以产出巨晶方解石矿为特点。本文在系统的野外地质调查和勘查评价基础上,分析了九龙巨晶方解石矿床的基本地质特征和控矿因素,探讨其成因。结果表明,区内方解石矿体呈层状、似层状及大脉状产于下二叠统茅口组(P1m)灰岩中,层控特点明显;成矿受围岩岩性和断裂的联合控制,开放空间后生热液充填交代成矿特点突出,属层控热液型矿床,新生代印度欧亚板块碰撞造山有关的陆内构造转换成矿可能是其关键机制。 展开更多
关键词 方解石矿床 巨晶方解石 矿床地质 控矿因素 九龙地区 禄劝县 滇中
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白云石晶体结构和地球化学特征对沉积环境响应:以扬子地台晚埃迪卡拉纪灯影组白云岩为例
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作者 杨志波 季汉成 +3 位作者 鲍志东 史燕青 赵雅静 向鹏飞 《地学前缘》 EI CAS CSCD 北大核心 2024年第3期68-79,共12页
受沉积环境的影响,在白云石形成过程中,其晶体结构与地球化学记录着相应的环境信息。本文以扬子地台晚埃迪卡拉纪灯影组杨坝剖面为例,通过系统采样研究了白云石的晶体结构和地球化学特征,明晰了基于岩石学和地球化学特征的灯影组沉积环... 受沉积环境的影响,在白云石形成过程中,其晶体结构与地球化学记录着相应的环境信息。本文以扬子地台晚埃迪卡拉纪灯影组杨坝剖面为例,通过系统采样研究了白云石的晶体结构和地球化学特征,明晰了基于岩石学和地球化学特征的灯影组沉积环境演化,归纳出了白云石晶体结构、地球化学特征与形成环境的耦合关系。结果表明:(1)杨坝剖面灯影组主要发育叠层石、核形石、泡沫棉石及凝块石等4种微生物白云岩和少量的晶粒、颗粒及角砾白云岩,垂向发育多期的微生物白云岩叠置韵律层,主要为局限台地潮坪相颗粒滩相。(2)地球化学分析表明,灯影组沉积演化过程为:一段主要为干旱气候、较高盐度的较浅水体,发育泥、粉晶白云岩沉积;二段下部水体加深、潮湿、低盐度,微生物白云岩最为发育;二段中上部水体总体相对较浅,湿度降低,盐度略增高;四段时水体先加深后迅速变浅,湿度逐渐降低,盐度亦逐渐增大。(3)研究区白云石晶体结构特征突显出典型的高Mg/Ca环境下流体参与形成,在干旱、高盐度的环境下,a/c值负偏,潮湿、低盐度的环境会导致晶胞参数a/c值正偏。有序度分布表明,随有序度的增加,a/c值逐渐靠近理想白云石。该结果不仅阐明准同生白云石晶体结构与形成环境关联,还揭示元古宇灯影组古海水环境特征。 展开更多
关键词 晶体结构 地球化学特征 沉积环境 扬子地台 灯影组
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石油沥青质结构及其对蜡分子结晶和沉积行为影响研究进展
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作者 雷云 李双双 +4 位作者 窦芮 朱浩然 刘学谦 王涵 于鹏飞 《当代化工》 CAS 2024年第7期1711-1715,共5页
深水油气资源将是21世纪全球油气资源开发的战略性接替区域。高沥青质含量作为深水油气资源的一个重要特征,对油气开采、储存运输和炼化过程都具有重要影响,尤其是沥青质与蜡在深水油气开发过程中的相互作用至关重要。以深水油气资源开... 深水油气资源将是21世纪全球油气资源开发的战略性接替区域。高沥青质含量作为深水油气资源的一个重要特征,对油气开采、储存运输和炼化过程都具有重要影响,尤其是沥青质与蜡在深水油气开发过程中的相互作用至关重要。以深水油气资源开采为契机,从沥青质结构角度,对沥青质结构表征、沥青质在油水界面的分布、沥青质对蜡结晶和原油胶凝及沉积过程影响等进行了系统论述。结果表明:沥青质结构特征可以采用原子力显微镜等进行表征,且多以多环芳烃为核心,直链或支烃基作为其支链;沥青质结构中表面官能团(亚砜基官能团、吡啶官能团等)对油水界面的稳定性影响不一;沥青质对蜡分子结晶和沉积行为影响,目前研究多集中在定性层面,微观机理分析有待深入。但分析沥青质与蜡的作用关系、作用过程及机理,将是未来主要的研究方向,能够为深水油气资源开采与输送提供理论参考和技术支持。 展开更多
关键词 深水油气资源 沥青质 结晶胶凝 沉积
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密封沉积处理对纤维素纳米晶体薄膜光学特性的调控
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作者 白辰雨 周宇星 +4 位作者 崔然然 陈志彪 梁栩鹏 马涛 宋弋 《食品工业科技》 CAS 北大核心 2024年第4期1-9,共9页
纤维素纳米晶体(Cellulose nanocrystal,CNC)在特定浓度下可自组装排列,赋予体系独特的光学性能。为阐明CNC薄膜形成过程中CNC自组装行为机制,本文通过分析CNC薄膜在宏观颜色、紫外可见光谱、偏振光学、微观形貌以及晶体结构等方面的变... 纤维素纳米晶体(Cellulose nanocrystal,CNC)在特定浓度下可自组装排列,赋予体系独特的光学性能。为阐明CNC薄膜形成过程中CNC自组装行为机制,本文通过分析CNC薄膜在宏观颜色、紫外可见光谱、偏振光学、微观形貌以及晶体结构等方面的变化,探究了密封沉积时间和CNC浓度对自然蒸发干燥薄膜内部胆甾相液晶形成与排列的影响。结果表明,当密封沉积时间延长至48 h后,CNC薄膜的结构色显色范围、胆甾相结构的长程有序性均得到明显提升。随着浓度的升高,CNC颗粒间距减小,相邻颗粒间扭转角增大,螺距被压缩,从480 nm减小至344 nm。此外,密封沉积处理对高浓度CNC悬浮液形成长程有序性胆甾相结构具有明显优势。本研究结果表明,延长密封沉积时间和提高CNC浓度可以提高薄膜中长程有序性的提高,并促进胆甾相结构域的形成。这进一步完善了CNC基智能包装材料制备的科学基础,对于新型可视化食品包装和检测材料的开发具有积极作用。 展开更多
关键词 纤维素纳米晶体 薄膜 密封沉积 自组装 胆甾相液晶
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瑶岗仙花岗质岩浆演化与两类钨矿化成因关系研究:黑云母和石榴子石矿物化学证据
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作者 郭聪 赵正 +2 位作者 刘战庆 吴小辉 刘洋 《矿床地质》 CAS CSCD 北大核心 2024年第1期102-127,共26页
瑶岗仙钨矿是南岭地区唯一一个石英脉型黑钨矿和矽卡岩型白钨矿均达大型规模的超大型矿床。两类钨矿体均产出于瑶岗仙复式花岗岩体的内外接触带,复式花岗岩体主要由中粒黑云母花岗岩和细粒二云母花岗岩组成,但多阶段岩浆演化与两类钨矿... 瑶岗仙钨矿是南岭地区唯一一个石英脉型黑钨矿和矽卡岩型白钨矿均达大型规模的超大型矿床。两类钨矿体均产出于瑶岗仙复式花岗岩体的内外接触带,复式花岗岩体主要由中粒黑云母花岗岩和细粒二云母花岗岩组成,但多阶段岩浆演化与两类钨矿化关系问题一直存在较大争议。文章以瑶岗仙矿区中粒黑云母二长花岗岩与细粒二云母二长花岗岩中的黑云母和石榴子石为切入点,对比研究两阶段花岗质岩浆氧逸度、挥发分、结晶分异程度,探讨了岩浆演化对钨矿化成因的制约。结果显示,细粒二云母二长花岗岩相较于中粒黑云母二长花岗岩中黑云母拥有更低的X_(Mg)值、更靠近Fe^(2+)端员、更低的Ⅳ(F)和更高的log(fHF/fHCl)^(fluid)值,指示其形成于还原性岩浆环境,且F含量更高,而后者更偏向氧化性,F含量偏低。两类花岗岩中的石榴子石均为岩浆成因的锰铝榴石,从中粒黑云母花岗岩至细粒二云母花岗岩,随着石榴子石中MnO含量的递增,CaO、FeO、MgO含量逐渐降低,Mn/(Mn+Fe)比值、Sc、Zn、Y、HREE含量随MgO降低而逐渐升高,表明细粒二云母二长花岗岩较中粒黑云母二长花岗岩演化程度更高,更有利于W的富集。石英脉型黑钨矿和矽卡岩型白钨矿成矿岩浆均具有低氧逸度和高F含量的特征,与细粒二云母二长花岗岩成岩环境一致。基于上述研究,结合矿区地球物理、地球化学、钻探信息,笔者建立了瑶岗仙矿床深部勘查模型,圈定了大根垄深部石英脉型黑钨矿找矿靶区、杨梅岭深部云英岩型找矿靶区、和尚滩南东侧矽卡岩型白钨矿找矿靶区。 展开更多
关键词 黑云母 石榴子石 氧逸度 挥发分 结晶分异 勘查模型 瑶岗仙钨矿
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