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1Non-antibiotic feed additives in diets for pigs:A review显示文摘A number of feed additives are marketed to assist in boosting the pigs' immune system, regulate gut microbiota, and reduce negative impacts of weaning and other environmental challenges.The most commonly used feed additives include acidifiers, zinc and copper, prebiotics, direct-fed microbials, yeast products, nucleotides, and plant extracts.Inclusion of pharmacological levels of zinc and copper, certain acidifiers, and several plant extracts have been reported to result in improved pig performance or improved immune function of pigs.It is also possible that use of prebiotics, direct-fed microbials, yeast,and nucleotides may have positive impacts on pig performance, but results have been less consistent and there is a need for more research in this area.Yanhong Liu Charmaine D.Espinosa Jerubella J.Abelilla Gloria A.Casas L.Vanessa Lagos Su A.Lee Woong B.Kwon John K.Mathai Diego M.D.L.Navarro Neil W.Jaworski Hans H.Stein 2018Animal Nutrition2018,,2:41
2Research on preservation and enrichment mechanisms of organic matter in muddy sediment and mudstone显示文摘Using multidiscipline methodologies, the differences in preservation and enrichment mechanisms of organic matter (OM) in muddy sediment and mudstone are investigated. In clay fractions, concentra- tions of TOC and chloroform bitumen “A” are significantly higher than those in coarser fractions. This indicates that clay minerals (CM) play an important role in enriching OM. The content of chloroform bitumen “A” increases obviously in the clay fraction, which reveals that dissolvable OM is the main composition of coalesce with clay minerals. Furthermore, TG and DTA data show that OM enrichment mechanisms and preservation forms have multiplicity. Several exothermic peaks in the DTA curves demonstrate that muddy sediment and mudstone contain a number of bioclasts and amorphous OM besides dissolvable OM. Through analyzing with XRD and DTA after mudstone samples were pretreated, the conclusions can be arrived at. Firstly, CM interlayer space of XRD curves and exothermic peaks of DTA curves both change as temperature increases. Secondly, the changes of CM interlayer space and exothermic peaks are concordant and stable around 350℃. All these are the features that OM enters CM interlayers to form stable organo-clay complexes. Therefore, the combination format of OM with CM is not only surface adsorption, partial OM enters CM interlayers to form stable organo-clay complexes. Finally, through the research on OM preservation forms and enrichment mechanisms in muddy sedi- ment and mudstone, the hydrocarbon-generation processes and the global carbon cycle and budget can be explained.CAI JinGong BAO YuJin YANG ShouYe WANG XingXin FAN DaiDu XU JinLi WANG AiPing 2007Science China Earth Sciences2007,50,5:25
3The incorporation of thermal methods in mineral magnetism of loess-paleosol sequences: a brief overview显示文摘The advantages of thermal methods for mineral-magnetic research of loess/paleosolsequences are illustrated in an introductory overview. When applying thermal methods, magnetiteand maghemite can be distinguished, something which is difficult with field-dependentmeasurements at room temperature. Also, variable low-temperature oxidation that is related toclimate may be quantified. Thirdly, grain-size estimates pertaining to the whole superparamagneticrange can be inferred from LT warming experiments and to a lesser extent from variable chemicalalteration during heating. Application of mineral-magnetic techniques may lead to thedevelopment of quantifiable proxy parameters for paleoclimate.A.J.VanVelzen M.J.Dekkers 1999Chinese Science Bulletin1999,44,S1:24
4Volcanism at the Permian-Triassic Boundary in South China and Its Effects on Mass Extinction显示文摘This paper discusses the clayrocks widespread at the Permian-Triassic boundary, which are mostly of volcanic origin. Volcanogenetic textures, structures and minerals such as high-temperature quartz are found in clayrocks at the Permian-Triassic boundary in many places. Thousands of microspherules have been collected from the Boundary clayrocks, many of which exhibit the typical features of the process from melting to cooling and solidification. indicating that they were formed by volcanic eruption or extraterrestrial impact. Volcanic effects on the Permian-Triassic mass extinction may be reflected in conodonts, algae and ammonoids. The Boundary clayrocks are found in many Permian-Triassic sections along the coast of Tethys. Their orighin remains to be studied.Yin Hongfu, Huang Siji, Zhang Kexin, Yang Fengqing, Ding Meihua, Bi Xianmei and Zhang Suxin China University of Geosciences, Wuhan, Hubei 1989Acta Geologica Sinica(English Edition)1989,63,4:22
5Characteristics and dynamic settings of the Central-east Asia multi-energy minerals metallogenetic domain显示文摘That more than 82 percent of proved sandstone-type uranium deposits coexist with proved oil-gas or coalfields in the world reflects the fact of coexistence and accumulation of multi-energy minerals including oil, gas, coal and uranium in the same basin. Especially, this phenomenon is most typical in the Central-east Asia energy basins. Across China, Mongolia and some central Asian countries, the giant Central-east Asia metallogenetic domain (CEAMD) stretches more than 6,000 km from Songliao Basin of China in the east to the Caspian Sea in the west. The multi-energy minerals distribution characteristics of the domain include: their spatial distribution is complicated and ordered; the ore-bearing horizon relates closely to the geographical region; the accumulation/mineralization and localization time is the same or close; the occurrence setting and accumulation/mineralization have close correlation; and they have rich provenance for all the minerals. All of these imply that they have close relations between each other under a unified geodynamic background. The exogenetic uranium mineralization process in CEAMD can be divided into five phases using time limits of 100 Ma, (50±2) Ma, 20±(2―4) Ma, 8―5 Ma. The major mineralization periods and their differences in each primary uranium-bearing basin are identical to the oil-gas accumulation and localization periods and phases in the same basin, and are also in response to regional tectonics and controlled in general by the regional geodynamic environment. For industrial application and commercial exploitation, it is suggested that an important period for coexistence, accumulation and localization of oil, gas, coal and uranium and their interaction mainly occur in the late/last and post basin evolution. Through generalized analysis and comparison of accumulation/mineralization environment of the energy basins in CEAMD, the authors propose that the relatively stable regional tectonic background and moderate (weaker) structural deformation probably are necessary for formation, coexistence and preservation of large and medium-scaled sandstone-type uranium ore deposits, oil-gas fields and coalfields, while basins in favor of coexistence and accumulation are those intracratonal, intermediary massif basins and corresponding reformed basins.LIU ChiYang QIU XinWei WU BoLin ZHAO HongGe 2007Science China Earth Sciences2007,50,z2:13
6南海盆海山火山碎屑岩的发现及其地质意义显示文摘海山火山碎屑岩是水下爆发性火山作用的产物。南海盆两座海山上发现火山碎屑岩表明海山顶部曾经一度高于PCL(压力补偿深度)。岩相学特征显示这些火山碎屑岩的胶结物主要为一混合相,包括粘土矿物和黑色铁质矿物等,这从一个侧面反映海山的正地形限制了粗粒外生碎屑到达海山顶部。岩石的单矿物组分、主量元素化学特征与同海山玄武质熔岩具有可比性,属碱性岩浆系列。计算获得海山平均最小下沉速率为0.06mm/年,最大可能达0.30mm/年。海山岩石的机械风化产物对周围海盆的沉积作用作出重要贡献。鄢全树 石学法 2009岩石学报2009,25,12:11
7A New Method for Experimental Determination of Compressional Velocities in Rocks and Minerals at High-pressure显示文摘A transmission-reflection-combined new method is presented for measuring elastic velocities of rocks and minerals at elevated temperature and pressure,which resolves the problems of gradients of temperature and pressure existing in original sample assembly with a pyrophyllite cube.At room temperature and pressure up to 3 GPa,single-crystal quartz and eclogite were used to provide samples under test,respectively.The results of this work agree with the previous measurements very well within the error range.By the use of this new technique,more precise and reasonable data of elastic properties of rocks and minerals at elevated temperature and pressure can be achieved.刘永刚 谢鸿森 郭捷 周文戈 徐济安 赵志丹 2000Chinese Physics Letters2000,17,12:11
8THE C^(14) AGE AND CYCLE OF SEDIMENTATION OF SOME SALINE LAKES ON THE QINGHAI-XIZANG PLATEAU显示文摘On the Qinghai-Xizang Plateau, there are a number of inland lakes that are the highest above sea level and the largest of their kind in the world. Most of them are structural lakes, their genesis and formation being influenced by structural factors. Amongst them there are more than 100 saline lakes in which are accumulated inexhaustible minerals such as halite, glauber salt, strintium minerals, borate, lithium mineral and sylvine.黄麒 蔡碧琴 余俊青 1981Chinese Science Bulletin1981,26,1:8
9Rock-weathering by lichens in Antarctic: patterns and mechanisms显示文摘Saxicolous species of lichens are able to induce and accelerate weathering of their rock substrate, and effects of lichens on substrate can be attributed to both physical and chemical causes. This paper is focused on biotic weathering actions of epilithic and endolithic species on the different rock types (sandstones and volcanogenic rocks) in Antarctica. The patterns, mechanisms, processes and neoformations of rock-weathering resulting from lichen colonization are expounded in detail. Furthermore, it is pointed out that, for a better understanding of the impacts of lichens on environments, the studies on the rate of biotic weathering and the comprehensive involvement of the lichen effects on weathering of natural rocks remain to be carried out in Antarctica.CHEN Jie1, Hans-Peter Blume2(1. Institute of Soil Science, CAS, Nanjing 210008, China 2. Institute of Plant Nutrition and Soil Science, University of Kiel, D-24098 Kiel, Germany) 2002Journal of Geographical Sciences2002,12,4:8
10Metamorphism of the East Sector of the Southern Qinling Orogenic Belt and Its Geological Significance显示文摘The east sector of the southern Qinling belt is, lithologically, composed mainly of metapelites,quartzites, marbles and small amount of metabasites and gneisses, whose protoliths are the Silurian, Devonian andless commonly the Sinian and Upper Palaeozoic. They have been subjected at least to two epochs of metamorphism.The early epoch belongs to progressive metamorphism which is centered on high amphibolite-granulite facies in theFuping area and changed outwards into low amphibolite facies (staurolite-kyanite zone), epidote amphibolite facies(garnet zone) and greenschist facies (chlorite and biotite zones), the metamorphic age of which is about 220-260 Ma.This early-epoch metamorphism belongs to different pressure types: the rocks from greenschist to low amphibolitefacies belong to the typical medium-pressure type which shows geothermal gradients of about 17-20℃/km and wasprobably produced by a crustal thickening process related to continental collision, and the high amphibolite-granulitefacies belongs to the low-pressure type which shows geothermal gradients of about 25-38℃/km and was probablyaffected by some magmatic heats. Based on the basic characteristics of the P-T paths of the different facies calculatedfrom the garnet zonations, it can be deduced that the metamorphism of medium-pressure facies series took place dur-ing an imbricated thickening process, rather than during the uplifting process after thickening. The late-epoch meta-morphism belongs to dynamic metamorphism of greenschist facies which is overprinted on the early-epoch meta-morphic rocks and is Yanshanian or Himalayan in age, probably related to intracontinental orogeny.WEI Chunjing YANG Chonghui ZHANG Shouguang 1999Acta Geologica Sinica(English Edition)1999,73,1:7
11Experiment of the ^(40)Ar/^(39)Ar dating of diagenetic illite in gas reservoirs显示文摘40Ar/39Ar dating of diagenetic illite has been performed to investigate gas reservoirs in the Sulige Gas Field of the northern Ordos Basin. A series of technical challenges were confronted, including illite purification, Ar recoil loss, and separation of diagenetic illite from detrital illite. Mineral growth ages for diagenetic illite were obtained by this experiment, from which the age of gas emplacement was deduced to be later than 169 Ma.WANG Longzhang, DAI Tongmo & PENG Ping’an State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, CAS, Guangzhou 510640, China Faculty of Resources, Chinese University of Geosciences, Wuhan 430074, China 2004Chinese Science Bulletin2004,49,S1:7
12REE Geochemistry in the Weathered Crust of Granites, Longnan Area,Jiangxi Province显示文摘Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. The rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.Wu Chengyu Huang Dianhao Guo Zhongxun Institute of Mineral Deposits, Chinese Academy of Geological Sciences, Beijing Geological Survey Party of South Jiangxi, Jiangxi Bureau of Geology and Mineral Resources, Ganzhou, Jiangxi 1990Acta Geologica Sinica(English Edition)1990,64,2:7
13Scientific and technical aspects of yogurt fortification:A review显示文摘Food fortification is one of the most important processes for improvement of the nutrients quality and quantity in food.It can be a very cost effective public health intervention.Due to the high consumption rate of dairy products such as yogurt,fortification of these products will effectively reduce or prevent diseases associated with nutritional deficiencies.The aim of this investigation is to study the technical aspects involved in production of different types of fortified yogurts and their role in disease prevention and correction of deficiencies.In this paper,firstly,fortification is defined and the main reasons behind carrying out this process are presented and then yogurt production process and a variety of minerals,vitamins,and functional ingredients which are used in the process are briefly discussed.©2015 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.Hadi Hashemi Gahruie Mohammad Hadi Eskandari Gholamreza Mesbahi Mohammad Amin Hanifpour 2015Food Science and Human Wellness2015,4,1:7
14Differentiation and accumulation of fluids in A-type granites: Evidence from accessory mineral study显示文摘The Laoshan A-type granite is a highly evolved granite body. The study on accessoryminerals indicates that there exist differentiation and accumulation of fluids during the late stage of evolution of the granite. The released fluids are rich in rare-earth elements (REE), high-field-strength elements (HFSE, such as Nb, Ta, Zr, Hf, Th, U, and Y) and volatiles (F, P, CO2, etc.). Owing to the presence of fluid, accessory mineral assemblages have changed during the evolution of A-type granite, and are especially characterized by large amounts of independent REE-Nb-Y-Th minerals present in the late facies. Late-accumulation of fluids may be of the general feature of A-type granites, at least of highly evolved ones.WANG Rucheng ZHAO Guangtao WANG Dezi LU Jianjun XU Shijin 2000Chinese Science Bulletin2000,45,17:7
15Advanced smart biomaterials and constructs for hard tissue engineering and regeneration显示文摘Hard tissue repair and regeneration cost hundreds of billions of dollars annually worldwide, and the need has substantially increased as the population has aged. Hard tissues include bone and tooth structures that contain calcium phosphate minerals.Smart biomaterial-based tissue engineering and regenerative medicine methods have the exciting potential to meet this urgent need. Smart biomaterials and constructs refer to biomaterials and constructs that possess instructive/inductive or triggering/stimulating effects on cells and tissues by engineering the material's responsiveness to internal or external stimuli or have intelligently tailored properties and functions that can promote tissue repair and regeneration. The smart material-based approaches include smart scaffolds and stem cell constructs for bone tissue engineering; smart drug delivery systems to enhance bone regeneration; smart dental resins that respond to pH to protect tooth structures; smart pH-sensitive dental materials to selectively inhibit acid-producing bacteria; smart polymers to modulate biofilm species away from a pathogenic composition and shift towards a healthy composition; and smart materials to suppress biofilms and avoid drug resistance. These smart biomaterials can not only deliver and guide stem cells to improve tissue regeneration and deliver drugs and bioactive agents with spatially and temporarily controlled releases but can also modulate/suppress biofilms and combat infections in wound sites. The new generation of smart biomaterials provides exciting potential and is a promising opportunity to substantially enhance hard tissue engineering and regenerative medicine efficacy.Ke Zhang Suping Wang Chenchen Zhou Lei Cheng Xianling Gao Xianju Xie Jirun Sun Haohao Wang Michael D.Weir Mark A.Reynolds Ning Zhang Yuxing Bai Hockin H.K.Xu 2018Bone Research2018,6,4:6
16The Conditions of Releasing Potassium by a Silicate- dissolving Bacterial Strain NBT显示文摘The potassium-releasing characteristics of a bacterium from different minerals were studied through pure culture and soil column experiments. The results showed that the strain NBT of tested strains had the highest potassium-releasing capacity. It released 35.2 mg/L after 7days of pure culture incubation at 28℃, 31.8% - 1203.7% more than other tested strains. Potassium released from the minerals was obviously affected by pH, aerobic condition, soil and mineral properties. The strain NBT had a much higher potential to release potassium in the pH 6.5 - 8.0 than other pHs. Living cell inoculation resulted in an increase of 84.8%- 127.9% compared with that of the dead cell inoculation. More aerobic condition produced more K than a less aerobic one. The potassium-releasing order was as follows: illite > feldspar> muscovite. Soil column experiment showed that the bacterial number increased from (2.6 - 3.0) × 106/g to (6.8 - 7.4) × 107/g. Soil available potassium content increased by 31.2- 33.6mg/kg in yellow-brown soil and 21.7mg/kg in paddy soil, when inoculated with the strain NBT, 290.6% and 185.5% increment of the dead cell inoculation soils respectively.SHENG Xia-fang,HE Lin-yan and HUANG Wei-yi(College of Natural Resources and Environmental Science, Nanjing Agricultural University, Nanjing 210095 , P.R.China) 2002Agricultural Sciences in China2002,1,6:6
17Hazardous elements and amorphous nanoparticles in historical estuary coal mining area显示文摘In Brazil, intense coal exploitation activities have led to environmental deterioration, including soil mortification, water contamination, loss of ecosystem, and atmospheric contamination. In addition,considerable quantities of sulfur-rich residues are left behind in the mining area; these residues pose grave environmental issues as they undergo sulfide oxidation reactions. When sulfur oxides come in contact with water, extreme acid leachate is produced with great proportions of sulfate, and hazardous elements(HEs), which are identified as coal drainage(CMD). CMD is an environmental pollution challenge, particularly in countries with historic or active coal mines. To prevent CMD formation or its migration, the source must be controlled; however, this may not be feasible at many locations. In such scenarios, the mine water should be collected, treated, and discharged. In this study, data from 2005 to2010 was gathered on the geochemistry of 11 CMD discharges from ten different mines. There are several concerns and questions on the formation of nanominerals in mine acid drainage and on their reactions and interfaces. The detailed mineralogical and geochemical data presented in this paper were derived from previous studies on the coal mine areas in Brazil. Oxyhydroxides, sulfates, and nanoparticles in these areas possibly go through structural transformations depending on their size and formation conditions. The geochemistry of Fe-precipitates(such as jarosite, goethite, and hematite) existent in the CMD-generating coal areas and those that could be considered as a potential source of hazardous elements(HEs)(e.g., Cr) were also studied because these precipitates are relatively stable in extremely low pH conditions. To simplify and improve poorly ordered iron, strontium, and aluminum phase characterization, field emission scanning electron microscopy(FE-SEM), high-resolution transmission electron microscopy(HR-TEM), micro-Raman spectroscopy, and X-ray diffraction(XRD) and sequential extraction(SE) studies were executed on a set CMD samples from the Brazilian mines. This study aimed to investigate the role of both nanomineral and amorphous phase distribution throughout the reactive coal cleaning rejects profile and HEs removal from the water mine to provide holistic insights on the ecological risks posed by HEs, nanominerals, amorphous phases, and to assess sediments in complex environments such as estuaries.Ana L.Duarte Kátia DaBoit Marcos L.S.Oliveira Elba C.Teixeira Ismael L.Schneider Luis F.O.Silva 2019Geoscience Frontiers2019,10,3:6
18THE AVAILABILITY OF PHOSPNORUS IN ROCK PNOSPNATE显示文摘Ⅰ. INTRODUCTION Deposits of rock phosphate and phosphate-bearing rocks have been discovered in great amount in China since liberation; this has led to the rapid development of China’s chemical industry of phosphatic fertilizers in recent years. Consequently, the utilization of powdered rock phosphate has become a mat-李庆逵 1966Chinese Science Bulletin1966,24,2:5
19Process mineralogy as a key factor affecting the flotation kinetics of copper sulfide minerals显示文摘The aim of this study is to apply process mineralogy as a practical tool for further understanding and predicting the flotation kinetics of the copper sulfide minerals. The minerals' composition and association, grain distribution, and liberation within the ore samples were analyzed in the feed, concentrate, and the tailings of the flotation processes with two pulp densities of 25 wt% and 30 wt%. The major copper-bearing minerals identified by microscopic analysis of the concentrate samples included chalcopyrite(56.2 wt%), chalcocite(29.1 wt%),covellite(6.4 wt%), and bornite(4.7 wt%). Pyrite was the main sulfide gangue mineral(3.6 wt%) in the concentrates. A 95% degree of liberation with d_(80) > 80 μm was obtained for chalcopyrite as the main copper mineral in the ore sample. The recovery rate and the grade in the concentrates were enhanced with increasing chalcopyrite particle size. Chalcopyrite particles with a d_(80) of approximately 100 μm were recovered at the early stages of the flotation process. The kinetic studies showed that the kinetic second-order rectangular distribution model perfectly fit the flotation test data. Characterization of the kinetic parameters indicated that the optimum granulation distribution range for achieving a maximum flotation rate for chalcopyrite particles was between the sizes 50 and 55 μm.Ataallah Bahrami Mirsaleh Mirmohammadi Yousef Ghorbani Fatemeh Kazemi Morteza Abdollahi Abolfazl Danesh 2019International Journal of Minerals,Metallurgy and Materials2019,26,4:4
20Study on Material Composition and REE-host Forms of Ion-type RE Deposits in South China显示文摘StudyonMaterialCompositionandREE-hostFormsofIon-typeREDepositsinSouthChinaZhangPeishan;TaoKejie;YangZhuming(InstituteofGeolog...张培善 陶克捷 杨主明 1995Journal of Rare Earths1995,13,1:4
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