检索结果-南通市图书馆

Fluoride contamination in groundwater:A global review of the status,processes,challenges,and remedial measures

Geoscience Frontiers 2024年第2期15卷 1-29页

作者： e.Shaji K.v.Sarath M.Santosh P.K.Krishnaprasad B.K.Arya Manisha S.Babu Department of Geology University of KeralaKariavattom CampusThiruvananthapuramKerala 695581India School of earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China Department of earth Science University of AdelaideAdelaideSA 5005Australia Department of Geology Central University of KeralaTejaswini HillsPeriyeKasaragodKerala 671316India

Groundwater pollution by fluoride is one of the prime concerns of the world population due to its toxicity,which results in adverse health *** this paper,we review the current scenario of the fluoride contamination of groundwater in various countries across the globe and its impact on human *** the last decade,several newly affected regions have been reported all over the world,with more than 100 countries affected by fluoride contamination in groundwater(concentration exceeding the acceptable limit of 1.5 mg/L defined by the World Health Organization).Fluoride poisoning is mainly due to the unsupervised ingestion of products for dental and oral hygiene and over-fluoridated drinking *** is estimated that more than 200 million people from different countries are affected by fluoriderelated groundwater issues and health *** highest among these are from the countries in Africa(38),Asia(28),and europe(24),followed by countries like South America(5),North America(3),and Australia(2).The source of fluoride in drinking water is primarily geogenic,together with forage,grasses and grains,tea,and anthropogenic *** countries affected were correlated with climatic zones and geological factors to gain insights into geospatial *** analyses show that most of the fluoride pollution-prone zones are located in high-grade metamorphic terranes with granitoid or alkaline intrusions,geothermal hot springs,and volcanic regions with arid or semi-arid climatic *** study also finds that children across the globe are more vulnerable than adults to fluoride *** review finds that,although there are efficient fluoride removal techniques,including filters with next-generation nanomaterials,to date,there has not been a single technique developed that can claim to be a practically robust solution for fluoride removal from drinking ***,we suggest developing next-generation filters that can retain essential miner

关键词： Fluoride Groundwater Water contamination WHO standards Climate zones Remediation Sustainable Development Goals

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Telluric iron assemblages as a source of prebiotic phosphorus on the early earth:Insights from Disko Island,Greenland

引用

Geoscience Frontiers 2024年第5期15卷 415-429页

作者： Oleg S.vereshchagin Maya O.Khmelnitskaya Larisa v.Kamaeva Natalia S.vlasenko Dmitrii v.Pankin vladimir N.Bocharova Sergey N.Britvin Saint Petersburg State University University Embankment 7-9St.Petersburg 199034Russia Udmurt Federal Research Center Ural BranchRussian Academy of SciencesIzhevsk 426067Russia Nanomaterial Research Center Kola Science CentreRussian Academy of SciencesApatity 184209Russia

Phosphorus is one of the key elements,which determined the emergence of primordial life on our *** source of prebiotic phosphorus was most likely to be easily soluble compounds containing phosphorus in the negative form of oxidation(e.g.,phosphides).The present paper is the first thorough investigation of phosphide-bearing mineral assemblages confined to telluric(terrestrial)native iron from volcanic rocks of Disko Island,*** speciation in given assemblages varies from the solid solution in native iron(up to 0.3 wt.%P),different phosphides–schreibersite Fe_(3)P,nickelphosphide Ni_(3)P,barringerite Fe_(2)P,and phosphates,including fluorapatite,anhydrous Fe-Na phosphates,phosphoran olivine and pyroxene(up to 1 wt.%P).The diversity of observed phosphorus speciation can be explained by the steep changes of redox conditions during subsurface crystallization of iron-phosphide-bearing *** on the available data on likely redox conditions on the early earth,we hypothesize that reactive prebiotic phosphorus may have originated from shallow crustal rocks.

关键词： Prebiotic phosphorus Native iron Phosphide Reduced mineral assemblages

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Design and synthesis of synthetic promoters for consistency of gene expression across growth phases and scale in ***

引用

Synthetic and Systems Biotechnology 2024年第2期9卷 330-339页

作者： Kristin v.Presnell Omar Melhem Sarah M.Coleman Nicholas J.Morse Hal S.Alper McKetta Department of Chemical engineering The University of Texas at Austin200E Dean Keeton St.Stop C0400AustinTX78712USA Institute for Cellular and Molecular Biology The University of Texas at Austin2500 Speedway AvenueAustinTX78712USA

Metabolic engineering and synthetic biology endeavors benefit from promoters that perform consistently(or robustly)with respect to cellular growth phase(exponential and stationary)and fermentation scale(microtiter plates,tubes,flasks,and bioreactors).However,nearly all endogenous promoters(especially in Saccharomyces cerevisiae)do not perform in this *** this work,a hybrid promoter engineering strategy is leveraged to create novel synthetic promoters with robustness across these *** a multi-dimensional RNA-seq dataset,promoters with specific phase dependencies were *** enriched with functional transcription factors were identified using MeMe *** motif-containing fragments could impart activity dependence in the opposing ***,we obtain two new promoters with high and consistent expression across both phases by increasing the exponential phase activity of the starting stationary-phase scaffold by 38 and 23-fold ***,we show that these promoters function consistently across various laboratory growth scales over time in a microtiter plate and in ***,this work presents and validates a new strategy for engineering promoters in *** with high levels of expression that are robust to cellular growth phase and the scale of the culture.

关键词： endogenous synthetic stationary

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genome-wide Studies Reveal Genetic Risk Factors for Hepatic Fat Content

引用

Genomics, Proteomics & Bioinformatics 2024年第2期22卷 57-68页

作者： Yanni Li eline H.van den Berg Alexander Kurilshikov Dasha v.Zhernakova Ranko Gacesa Shixian Hu esteban A.Lopera-Maya Alexandra Zhernakova Lifelines Cohort Study vincent e.de Meijer Serena Sanna Robin P.F.Dullaart Hans Blokzijl eleonora A.M.Festen Jingyuan Fu Rinse K.Weersma Department of Gastroenterology and Hepatology University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Genetics University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China Laboratory of Genomic Diversity Center for Computer TechnologiesITMO UniversitySaint Petersburg 199034Russia Institute of Precision Medicine the First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Department of Surgery Section of Hepatobiliary Surgery and Liver TransplantationUniversity of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of endocrinology University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Pediatrics University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands 不详

Genetic susceptibility to metabolic associated fatty liver disease(MAFLD)is complex and poorly *** characterization of the genetic background of hepatic fat content would provide insights into disease etiology and causality of risk *** performed genome-wide association study(GWAS)on two noninvasive definitions of hepatic fat content:magnetic resonance imaging proton density fat fraction(MRI-PDFF)in 16,050 participants and fatty liver index(FLI)in 388,701 participants from the United Kingdom(UK)Biobank(UKBB).Heritability,genetic overlap,and similarity between hepatic fat content phenotypes were analyzed,and replicated in 10,398 participants from the University Medical Center Groningen(UMCG)Genetics Lifelines Initiative(UGLI).Meta-analysis of GWASs of MRI-PDFF in UKBB revealed five statistically significant loci,including two novel genomic loci harboring CReB3L1(rs72910057-T,P=5.40e−09)and GCM1(rs1491489378-T,P=3.16e−09),respectively,as well as three previously reported loci:PNPLA3,TM6SF2,and *** of FLI in UKBB identified 196 genome-wide significant loci,of which 49 were replicated in UGLI,with top signals in ZPR1(P=3.35e−13)and FTO(P=2.11e−09).Statistically significant genetic correlation(rg)between MRI-PDFF(UKBB)and FLI(UGLI)GWAS results was found(rg=0.5276,P=1.45e−03).Novel MRI-PDFF genetic signals(CReB3L1 and GCM1)were replicated in the FLI *** identified two novel genes for MRI-PDFF and 49 replicable loci for *** a difference in hepatic fat content assessment between MRI-PDFF and FLI,a substantial similar genetic architecture was *** is identified as an easy and reliable approach to study hepatic fat content at the population level.

关键词： Hepatic fat content MAFLD Genome-wide association study Fatty liver index Magnetic resonance imaging proton density fat fraction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phanerozoic co-evolution of O2-CO2 and ocean habitability

引用

National Science Review 2024年第6期11卷 18-21页

作者： Zunli Lu Rosalind e.M.Rickaby Jonathan L.Payne Ashley N.Prow Department of earth & environmental Sciences Syracuse University Department of earth Sciences University of Oxford Department of earth and Planetary Sciences Stanford University

Atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of earth have been hotly debated, but are generally considered independently.

关键词： CO2-CONCeNTRATING MeCHANISM OXYGeN evOLUTION ANOXIA

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

evaluating the biosignature potential of ammonium in Proterozoic red beds and implications for the search for life on Mars

引用

地球与行星物理（英文） 2024年第6期8卷 836-853页

作者： eva e. Stüeken Philip Fralick Stephen Hillier Anthony R. Prave School of earth and environmental Sciences University of St Andrews St Andrews KY16 9TS UK Department of Geology Lakehead University Thunder Bay ON P7B 5E1 Canada The James Hutton Institute Craigiebuckler Aberdeen AB15 8QH UK Department of Soil and environment Swedish University of Agricultural Sciences (SLU) SE-75007 Uppsala Sweden

Over the past two decades, it has become increasingly apparent that early Mars may once have been warmer, wetter and more habitable for microbial life than it is today, which has spurred discussions about potential biosignatures that may be preserved in Martian sediments. An impediment to this line of research is the pervasive oxidation of Mars’ surface due to photochemical oxidants that have likely destroyed remnants of organic matter. Here, we investigate whether nitrogen (N) transferred from biomass to phyllosilicate minerals during diagenesis can be preserved in oxidized mudrocks. We investigate two sequences of terrestrial Proterozoic red beds, namely the Sibley Group (1.4 Ga) in Canada and the Stoer Group (1.2 Ga) in Scotland, and we find enrichments in authigenic N in the range of several tens of ppm in both units. The highest concentrations (ca. 100 ppm on average) are found in the most desiccated red beds of the Stoer Group, concurrent with enrichments in potassium (K). We discuss similarities and differences between the two sets of rocks with regards to salinity, pH, biological productivity and K-metasomatism, and we conclude that the ideal mechanism for the preservation of biogenic N in red beds may be in-situ release of ammonium from microbial mats into the clay substrate, possibly facilitated by early diagenetic, biologically induced illitization. Illite and smectite have been observed on Mars, and experiments suggest that Martian waters contained moderate amounts of dissolved K. Hence, it is conceivable that a similar K and N enrichment process could have occurred as to what we document for the Proterozoic, preserving evidence of life that may have survived to the modern day.

关键词： red beds biosignature Mars nitrogen ammonium clay minerals

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modelling the brittle rock failure by the quaternion-based bonded-particle model in DeM

Rock Mechanics Bulletin

引用

Rock Mechanics Bulletin 2024年第2期3卷 87-95页

作者： Tao Zhao Philip e.F.Collins Department of Civil and environmental engineering Brunel University LondonLondonUB83PHUnited Kingdom

This paper presents an investigation of brittle rock failure by the quaternion-based bonded-particle model in discrete element method(DeM).Unlike traditional approaches that utilize euler angles or rotation matrices,this model employs unit quaternions to represent the spatial rotations of *** method simplifies the rep-resentation of 3D rotations,providing a more intuitive framework for modelling complex interactions in granular *** numerical model was validated by the uniaxial compression tests on rock,with good agreement with well-documented experimental data in terms of the rock uniaxial compression strength(UCS)and failure *** loading,the rock sample demonstrated a linear-elastic response at an axial strain of smaller than 0.45%.However,as internal bond breakage accumulated,this linear relationship weakened,and the stress-strain curve began to deviate from its initial linear *** bond breakage and the overall deformation of the rock were primarily controlled by the shear bonding *** UCS was achieved at an axial strain of 0.625%,at which point the internal shear bonding force chains were predominantly aligned *** brittle failure occurred when the internal damage of solids nucleated to form an interconnected failure plane,accompanied by a sharp rise in the internal damage *** area of failure plane increased with the loading strain rate,gradually transforming the failure pattern from the local damage to a complete fragmentation.

关键词： Brittle failure Quaternion DeM bonded model Uniaxial compression test Rate dependent Internal damage

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

expanded Porphyrin exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

引用

CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alexey v.Kuzmin Maxim A.Faraonov evgenii N.Ivanov Salavat S.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri v.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of Solid-State Physics RAS 142432 Chernogolovka Research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo Institute for Advanced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMDeA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rigidity Symmetry Line for Thermodynamic Fluid equations-of-State

引用

Journal of Modern Physics 2024年第5期15卷 613-633页

作者： Leslie v. Woodcock Department of Physics University of Algarve Faro Portugal

We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by percolation transitions. The state functions density ρ(p,T), and Gibbs energy G(p,T), of fluids, e.g. CO2, H2O and argon exhibit a symmetry characterised by the rigidity, ω = (dp/dρ)T, between gaseous and liquid states along any isotherm from critical (Tc) to Boyle (TB) temperatures, on either side of the supercritical mesophase. Here, using experimental data for fluid argon, we investigate the low-density cluster physics description of an ideal dilute gas that obeys Dalton’s partial pressure law. Cluster expansions in powers of density relate to a supercritical liquid-phase rigidity symmetry (RS) line (ω = ρrs(T) = RT) to gas phase virial coefficients. We show that it is continuous in all derivatives, linear within stable fluid phase, and relates analytically to the Boyle-work line (BW) (w = (p/ρ)T = RT), and to percolation lines of gas (PB) and liquid (PA) phases by: ρBW(T) = 2ρPA(T) = 3ρPB(T) = 3ρRS(T)/2 for T TB. These simple relationships arise, because the higher virial coefficients (bn, n ≥ 4) cancel due to clustering equilibria, or become negligible at all temperatures (0 T TB) within the gas phase. The Boyle-work line (p/ρBW)T is related exactly at lower densities as T → TB, and accurately for liquid densities, by ρBW(T) = −(b2/b3)T. The RS line, ω(T) = RT, defines a new liquid-density ground-state physical constant (ρRS(0) = (2/3)ρBW(0) for argon). Given the gas-liquid rigidity symmetry, the entire thermodynamic state functions below TB are obtainable from b2(T). A BW

关键词： Liquid-State Theory Cluster Physics Percolation Lines Fluid Thermodynamics Boyle Line Rigidity-Symmetry Line

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Doping effect of Poly(vinylidene fluoride) on Carbon Nanofibers Deduced by Thermoelectric Analysis of Their Melt Mixed Films

引用

Chinese Journal of Polymer Science 2024年第11期 1802-1810页

作者： A.J.Paleo v.M.Serrato J.M.Mánuel O.Toledano e.Mu?oz M.Melle-Franco B.Krause P.P?tschke K.Lozano 2C2T-Centre for Textile Science and Technology University of Minho Campus de Azurém Florida Institute of Technology The Aerospace Corporation Department of Condensed Matter Physics and Institute of Research on electron Microscopy and Materials(IMeYMAT) Faculty of Sciences University of Cádiz CICeCO – Aveiro Institute of Materials Department of Chemistry University of Aveiro UNeD-Universidad Nacional de educación a Distancia Facultad de Física Pontificia Universidad Católica de Chile Leibniz-Institut für Polymerforschung Dresden e.v.IPF Department of Mechanical engineering University of Texas Rio Grande Valley

The effect of temperature on the electrical conductivity （σ） and Seebeck coefficient （S） of n-type vapor grown carbon nanofibers （CNFs）and poly（vinylidene fluoride）(PvDF) melt-mixed with 15 wt%of those CNFs is *** 40°C,the CNFs show stable n-type character (S=-4.8μv·K-1) with anσof ca.165 S·m-1,while the PvDF/CNF composite film shows anσof ca.9 S·m-1and near-zero S (S=-0.5μv·K-1).This experimental reduction in S is studied by the density functional tight binding （DFTB） method revealing a contact electron transfer from the CNFs to the PvDF in the ***,in the temperature range from 40°C to 100°C,theσ（T） of the CNFs and PvDF/CNF film,successfully described by the 3D variable range hopping （vRH） model,is explained as consequence of a thermally activated backscattering *** the contrary,the S（T）from 40°C to 100°C of the PvDF/CNF film,which satisfactorily matches the model proposed for some multi-walled carbon nanotube （MWCNT）doped mats;however,it does not follow the increase in S（T） found for *** these findings are presented with the aim of discerning the role of these n-type vapor grown carbon nanofibers on theσand S of their melt-mixed polymer composites.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：