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Studies on the Hazardous Effects and the Maximum Allowable Concentration of Pyrophyllite Dust
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作者 ZHANG WEN-CHANG ZHANG QI-FEN SONG ZHI-FANG(Deportment of Occupotional Health, Fujian Medical University, 88 Jiaotong Road, Fuzhou 350004, China)(Division of Pneumoconiosis, Zhejiang Medical University, Yan an Road, Hangzhou 310006, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1997年第4期377-386,共10页
Pyrophyllite (H2Al2,Si4 O22, ) dust (P-dust) is a mixture of silica (10-40% ), differentproportions of a luminium oxide (Al2O3 ), and various metal compounds. People with occupa-tions known to be associated with expos... Pyrophyllite (H2Al2,Si4 O22, ) dust (P-dust) is a mixture of silica (10-40% ), differentproportions of a luminium oxide (Al2O3 ), and various metal compounds. People with occupa-tions known to be associated with exposure to P-dust include miners, other industrial workersand persons engaged in artistic carving. Currently, little is known about pyrophyllite pneumo-coniosis from P-dust. This study was designed to investigate the hazardous effects of P-dustand to suggest a maximum allowable concentration (MAC) of the dust.This.study included four parts: (i) Occupational epidemiology surveys in 781 workersfrom 1 pyrophyllite mine (PM) and four pyrophyllite carving mills (PCM), with a registra-tion rate of 98 %. (ii) In vitro studies: Six groups of rats were expeed to different levels ofP-dust; the cytotoxicity of P-dust on rat alveolar macrophages (AM) was investigated by de-termining the potassium'content of AM and the activity levels of lactate dehydrogenase (LDH)in AM culture fluid. (iii) Mineralogical analysis of P-dust: The contents of silica (SiO2 ), alu-minium (Al), ferrum (Fe), niikel (Ni), zinc (Zn) and copper (Cu) in hath PM-dust andPCMdust were determined. (iv ) Determination of P-dust MAC: Using the life-talbemethod, an investigation of the hygiene standard of P-dust was carried out in 625 workers ex-POSed to either PM-dust or PCM-dust, uPon whom routine radiographs were Performed.The results suggest that the risk of developing pneumoconiosis from pyrophyllite dust issignificantly higher for PM workers than for PCM workers. The prevalence rate of PCM-dustpneumoconiosis is significantly higher in men than in women. The content of SiO2 and AlO3in the mixture of P-dust is the most important factor in the etiology of pyrophyllitosis. De-pending on the different P-dust MAC values, we suggest that 2 rng/m3 and 4 mg/m' shouldbe considered as the MAC for PM-dust and PCM-dust, respectively, and 3 mg/m' fOr P-dust. We believe that establishing different hygiene standards is more accurate even thoughworkers are exposured to the 'same' dust 展开更多
关键词 PCM Studies on the Hazardous Effects and the Maximum Allowable Concentration of pyrophyllite Dust PM ZHANG SiO
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Effect of Pyrophyllite Addition on Properties of Lightweight Insulation Refractory Materials
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作者 CHEN Ruoyu LI Yuanbing +4 位作者 XIANG Ruofei LI Shujing FAN Xiafei LI Yawei SANG Shaobai 《China's Refractories》 CAS 2017年第3期38-42,共5页
To solve the problem of over-high density of lightweight insulation refractory bricks prepared with fly ash, new lightweight insulation refractory materials with density 〈 0. 89 g · cm^-3 were .synthesized using... To solve the problem of over-high density of lightweight insulation refractory bricks prepared with fly ash, new lightweight insulation refractory materials with density 〈 0. 89 g · cm^-3 were .synthesized using pyrophyl-lite, .fly ash, and Suzhou clay as the main starting materials and saw dast as the pore forming substance, and controlling the addition of the pyrophyllite (20%, 30% , and 40% by mass ) and the treating temperature (1 250, 1 300, 1 350, and 1 400 ℃ ). The synthesized materials were characterized by the XRD, SEM and the thermal conductivity measuring in.strument. The results show at pyrophyllite addition of 30% and treat temperature of l 400 ℃ , the material can achieve linear shrinkage of 6. 6%, apparent porosity of 57%, bulk density of 0. 75 g · cm^-3, compressive strength of 2.7 MPa, and thermal conductivity at 350 ℃ of 0. 152 -0. 216 W·( m·K)^-1.This indicates that the pyrophyllite decomposition at high temperatures forms mullite and amorphous quartz introducing volume expansion, which counteracts some shrinkage at high temperatures. So it is feasible to use pyrophyllite, fly ash waste and clay to prepare lightweight insulation refractory materials. 展开更多
关键词 pyrophyllite fly ash lightweight insulation refractory materials thermal conductivity bulk density compressive strength
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GEOTECTONIC BACKGROUND OF PYROPHYLLITE MINERALIZATION AND ORE-BEARING VOLCANIC FORMATION IN SOUTHEASTERN COASTAL AREAS,CHINA
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作者 Wang Ling(Changsha Institute of Geotectonics, Academia Sinica, Changsha, 410013, Hunan, China)Liu Dongshen (Geologic Institute, National Construction Material Industry Bureau, 100010, Beijing, China) 《Geotectonica et Metallogenia》 1996年第Z1期46-50,共5页
GEOTECTONIC BACKGROUND OF PYROPHYLLITE MINERALIZATIONAND ORE-BEARING VOLCANICFORMATION IN SOUTHEASTERNCOASTAL AREAS, CHINAWang Ling(Changsha Institute of Geotectonics, Academia Sinica, Changsha, 410013, Hunan, China)L... GEOTECTONIC BACKGROUND OF PYROPHYLLITE MINERALIZATIONAND ORE-BEARING VOLCANICFORMATION IN SOUTHEASTERNCOASTAL AREAS, CHINAWang Ling(Changsha Institute of Geotectonics, Academia Sinica, Changsha, 410013, Hunan, China)Liu Dongshen (Geologic Institute, National Construction Material Industry Bureau, 100010, Beijing, China)pyrophyllite, Diwa structure, nonmetallic metailogeny, ore-bearing forma-tion , the Sountheastern Coastal Areas, ChinaThe volcanic gas-liguid type of pyrophyllite deposits in the SoutheasternCoastal areas, China are the product of tectono-magama-volcanism in Diwa regions. The pyro-phyllite ore-bearing volcanic formation were formed in the maximum-mobility period of Diwa, which are mainly the Late Jurassic strata and are secondly the Early Cretaceous volcanic-sedi-mentary rock series strata. The lithology of the host rock is mainly rhyolitic crystal-vitric tuff, and the chemical composition is characterized by high silicon rich alumium and low iron, be-longing to the 展开更多
关键词 pyrophyllite DIWA structure nonmetallic metailogeny ore-bearing forma-tion the Sountheastern Coastal Areas China
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BASIC TYPES AND MINERALIZATION OF PYROPHYLLITE DEPOSITS OF VOLCANIC GAS-LIOUID ALTERATION GENESIS
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《Geotectonica et Metallogenia》 1994年第Z2期116-117,共2页
关键词 GAS BASIC TYPES AND MINERALIZATION OF pyrophyllite DEPOSITS OF VOLCANIC GAS-LIOUID ALTERATION GENESIS
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High-temperature phases of pyrophyllite and their evolutionary characteristics
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作者 WANG Ling and ZHANG Zhenyu1. Changsha Institute of Geotectonics, Chinese Academy of Sciences, Changsha 410013, China 2. Institute of Geology, Chinese Academy of Sciences, Beijing 100029, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第2期140-144,共5页
WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than... WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1150℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain. 展开更多
关键词 pyrophyllite high-temperature PHASE PHASE tranformation pyrophyllite ANHYDRITE MULLITE cristobalite.
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Formation of a Hydrothermal Kaolinite Deposit from Rhyolitic Tuff in Jiangxi, China
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作者 Ye Yuan Guanghai Shi +4 位作者 Mengchu Yang Yinuo Wu Zhaochong Zhang Anjie Huang Jiajing Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2014年第3期495-505,共11页
The Longmen kaolinite deposit is one of the largest hydrothermal clay deposits of Ganxi volcanic basin(northern Wuyi Mountain area, China). The pristine host rocks are rhyolitic crystal-vitric tuff and minor lapilli... The Longmen kaolinite deposit is one of the largest hydrothermal clay deposits of Ganxi volcanic basin(northern Wuyi Mountain area, China). The pristine host rocks are rhyolitic crystal-vitric tuff and minor lapilli tuff from the Late Jurassic Ehuling Formation. The ore consists of kaolin-group minerals(kaolinite, dickite), pyrophyllite with minor quartz, sericite, pyrite, etc.. From the host rocks to the transition zones(altered rocks) then to the vein ores, contents of SiO2 and TFe2O3 decrease, whereas Al2O3 and LOI increase, consistent with the contents increase of kaolin minerals and pyrophyllite in the samples. The total REE abundances of the ores are much lower than that of the host and altered rocks, Rb, Nb, Nd, Zr, Ti and Y are significantly depleted. Apparent zoning features of bulk geochemistry and mineral component reflect that the kaolinite deposit occurred at the expense of the host rock by ascending hydrothermal fluids with distinct removal of SiO2, TFe2O3, Na2O, K2O. According to the mineral assemblage, the formation temperature of this deposit falls within the range of 270–350 ℃. With regard to the industrial applications, the kaolinized ores are suitable for use in ceramics and gemologic materials crafted for seal stones. Moreover, in mineralogical terms, this deposit is also proved to be an excellent example for studying channeled hydrothermal alterations of rhyolitic tuff. 展开更多
关键词 China GEOCHEMISTRY hydrothermal alteration JIANGXI KAOLINITE pyrophyllite.
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Orientating structure of hydroxyls in 2 : 1 phyllosilicate
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作者 WANG Lin ZHANG Zhenyu 《Chinese Science Bulletin》 SCIE 1997年第4期321-324,共4页
ABBOTT et al. considered that there might be two types of hydroxyls with different site energies in the dioctahedral silicates. Giese holds a similar opinion. However, so far no detailed research has been done on the ... ABBOTT et al. considered that there might be two types of hydroxyls with different site energies in the dioctahedral silicates. Giese holds a similar opinion. However, so far no detailed research has been done on the orientating features, types and genesis of orientations 展开更多
关键词 orientating STRUCTURE of HYDROXYLS 2 PHYLLOSILICATE dioctahedral MINERALS trioctahedral MINERALS pyrophyllite.
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