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建筑设计决策对工程造价的影响分析

工程与建设 2024年第4期38卷 990-992页

作者：陈艳梅广州机场建设投资集团有限公司广东广州510000

在建筑工程的实施过程中,设计决策是影响工程造价的关键因素之一。通过对某具体建筑工程造价的深入分析,本文旨在揭示建筑设计决策如何影响工程造价,并探讨如何通过优化设计决策来控制和降低工程造价。本文详细分析了建筑工程造价中的... 详细信息

在建筑工程的实施过程中,设计决策是影响工程造价的关键因素之一。通过对某具体建筑工程造价的深入分析,本文旨在揭示建筑设计决策如何影响工程造价,并探讨如何通过优化设计决策来控制和降低工程造价。本文详细分析了建筑工程造价中的常见问题,如设计阶段成本估算不准确、材料选择与采购成本高昂、施工过程中变更管理不当以及合同管理与风险控制缺失等,并通过BIM技术、精益建造理念、IPD模式和绿色建筑设计策略等建筑设计决策创新模式,探讨了它们在实际工程造价控制中的应用,对提高建筑工程经济效益具有重要意义。

关键词：建筑设计决策工程造价 BIM技术精益建造

Syntheses and Crystal Structures of Five Sr^(Ⅱ)-Ln^(Ⅲ)(Ln=Nd,Pr,Er) Heterometallic Coordination Polymers

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1859-1867页

作者： CAO yan-Yuan chen yan-mei LIU Wei LI Ya-Hong Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow University

Five novel SrⅡ-LnⅢ heterometallic coordination polymers based on pyridine-2,6- dicarboxylic acid （H2pda） and imidazole （im）, namely, [LnSr（pda）3（H2O）5]-Him·C2H5OH·3H2O （Ln = Nd （1）; Pr （2））, [Ln2Sr（pda）6（H2O）5]-4Him·C2H5OH·5H2O （Ln = Nd （3）; Pr （4））, and [ErSr（pda）3（H2O）4].Him-3.5H2O （5）, have been prepared and structurally characterized. X-ray crystallographic analyses revealed that these complexes display three varieties of l-D chain structures. Several types of hydrogen bonding interactions are found for 1-5, which connect the 1 -D chain structures to form 2-D suoramolecular networks.

关键词： heterometallic coordination polymers strontium lanthanide crystal structure

Temperature Distribution of Iron Ore Pellet Bed in Grate

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Journal of Iron and Steel Research International 2012年第2期19卷 7-11页

作者： FENG Jun-xiao XIE Zhi-yin chen yan-mei School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

The temperature distribution of iron ore pellet bed in grate has a significant effect on pellet production and quality control, but the related work is scarce. A well-designed test was successfully carried out by means of tracking measurement and the temperature distribution and variation in pellet layers were obtained. The effects of blast tem- perature, blast velocity and oxidation reaction on the pellet layer temperature were studied. According to the analy- sis, the inlet air temperature in the up-draught drying zone （UDD） and blast temperature in the Preheating I （PH I） zone should be raised, and the length of the down-draught drying zone （DDD） should be properly increased.

关键词： grate iron ore pellet bed temperature distribution industrial test

太行山坡地4种植物篱及不同篱带位置土壤抗蚀性研究

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环境生态学 2024年第5期6卷 82-92页

作者：郭文芳高飞陈艳梅河北师范大学地理科学学院河北省环境变化遥感识别技术创新中心河北省环境演变与生态建设重点实验室河北石家庄050024

研究太行山坡地不同植物篱及篱带前、篱带内、篱带后土壤抗蚀性的变化特征,为该区水土保持和退化坡地生态恢复工作提供科学支撑。以枸杞(Lycium chinense)、欧李(Cerasus humilis)、薄荷(Mentha canadensis)、连翘(Forsythia suspense)... 详细信息

研究太行山坡地不同植物篱及篱带前、篱带内、篱带后土壤抗蚀性的变化特征,为该区水土保持和退化坡地生态恢复工作提供科学支撑。以枸杞(Lycium chinense)、欧李(Cerasus humilis)、薄荷(Mentha canadensis)、连翘(Forsythia suspense)4种植物篱及空白裸地为研究对象,选择9个土壤抗蚀性指标,运用主成分分析方法进行土壤抗蚀性评价。结果表明:1)植物篱样地的土壤容重、可蚀性K值普遍低于裸地,孔隙度、持水量、养分含量、土壤颗粒分形维数及水稳性指数普遍高于裸地,且各指标在植物篱带前、带内、带后具有显著差异性。2)主成分分析结果表明:土壤容重、毛管孔隙度、饱和持水量、有机质是评价该研究区土壤抗蚀性的最佳指标,植物篱样地的土壤抗蚀性优于裸地,整体表现为枸杞>连翘>欧李>薄荷>裸地,且植物篱带内土壤抗蚀性强于带前、带后。3)土壤抗蚀指数与毛管孔隙度、全氮、有机质、土壤颗粒分形维数存在显著正相关关系(p<0.05),与可蚀性K值存在显著负相关关系(p<0.05)。综上,植物篱种植可一定程度上提高土壤抗蚀性,且4种植物篱中,枸杞的效果较好。建议该区域可优先选用枸杞作为生态修复物种,增强坡地水土保持能力和抗蚀性。

关键词：植物篱土壤抗蚀性主成分分析太行山

Polymorphisms of the Vitamin D Receptor Gene and SexDifferential Associations with Lipid Profiles in Chinese Han Adults

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Biomedical and Environmental Sciences 2022年第2期35卷 115-125页

作者： chen yan mei XU Ping WANG Zhou Tian ZHU Yu mei GONG Chun mei HUANG Chang Hua LIU Xiao Li ZHOU Ji Chang School of Public Health(Shenzhen) Sun Yat-sen UniversityShenzhen 518100GuangdongChina Shenzhen Center for Chronic Disease Control Shenzhen 518020GuangdongChina Shenzhen Qilinshan Sanatorium Shenzhen 518055GuangdongChina Guangdong Province Engineering Laboratory for Nutrition Translation Guangzhou 510080GuangdongChina

Objective To explore the association of single nucleotide polymorphisms(SNPs)of the vitamin D receptor gene(VDR)with circulating lipids considering gender *** Of the Han Chinese adults recruited from a health examination center for inclusion in the study,the circulating lipids,25-hydroxyvitamin D(25OHD),and other parameters were *** VDR SNPs of Cdx2(rs11568820),Fok1(rs2228570),Apa1(rs7975232),and Taq1(rs731236)were genotyped with a qPCR test using blood DNA samples,and their associations with lipids were analyzed using logistic *** In the female participants(n=236 with dyslipidemia and 888 without dyslipidemia),multiple genotype models of Fok1 indicated a positive correlation of B(not A)alleles with LDLC level(P<0.05).In the male participants(n=299 with dyslipidemia and 564 without dyslipidemia),the recessive model of Cdx2 and the additive and recessive models of Fok1 differed(P<0.05)between the HDLC-classified subgroups,respectively,and Fok1 BB and Cdx2 TT presented interactions with 25OHD in the negative associations with HDLC(P<0.05).Conclusion In the Chinese Han adults included in the study,the Fok1 B-allele of VDR was associated with higher LDLC in females,and the Fok1 B-allele and the Cdx2 T-allele of VDR were associated with lower HDLC in *** interaction of VD and Fok1 BB or Cdx2 TT in males synergistically decreased HDLC levels.

关键词： Vitamin D Vitamin D receptor Gene polymorphism Lipid Dyslipidemia

Mechanism of Slag Composition Change During Electroslag Remelting Process

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Journal of Iron and Steel Research International 2011年第10期18卷 24-28,53页

作者： ZHAO Jun-xue chen yan-mei LI Xiao-ming CUI Ya-ru LU Xiao-tao School of Metallurgical Engineering Xi＇an University of Architecture and Technology Xi＇an 710055 Shannxi China

The mass loss rate of CaF2-CaO-Al2O3-SiO2-MgO slag system originated from ANF-6 was studied with CaF2, CaO, Al2O3, SiO2 or MgO content as variables. The method of quadratic regression orthogonal design was used for the design and analysis of the experiment. The experimental results indicated that mass loss rate of slag can be increased by 6% with CaF2 changing from 50%to 65%. Mass loss increases with SiO2 , Al2O3 and MgO adding and decreases with CaO content increasing. Because of the reaction between oxide and fluoride in the slag pool, apparent mass loss of CaF2-Al2O3 CaO-SiO2 MgO slag system appears at melting point. This will cause obvious composition change of electroslag. In addition, the segregation occurs in the slag skin forming process. This is another reason causing the composition change of electroslag.

关键词： electroslag DSC-TG analysis quadratic regression orthogonal design composition change

Synthesis, Structure and Luminescent Properties of Three 1D Chain Rare Earth Complexes

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Chinese Journal of Structural Chemistry 2019年第6期38卷 977-984页

作者： chen yan-mei LI Lian QIU Lei LI Qing ZHANG Wan-Ju Hubei Key Laboratory for Processing and Application of Catalytic Materials College of Chemistry and Chemical EngineeringHuanggang Normal University

Three 1 D chain coordination polymers [Ln(pydc)2(H2 O)2]n·n Him(Ln = Dy(1), Gd(2), Sm(3), H2 pydc = pyridine-2,5-dicarboxylic acid, Im = imidazole), were solvothermally synthesized by the reaction of pyridine-2,5-dicarboxylic acid(H2 pydc), Ln(Ⅲ) salts and imidazole. They have been characterized by X-ray single-crystal diffraction, IR spectra, TGA analysis and elemental analysis. Structural analyses revealed that complexes 1~3 have similar 1 D chain structures and belong to P1 space group. It is noteworthy that complexes 1~3 exhibited excellent thermal stability and no weightlessness below 117 ℃. Meanwhile, 1 and 3 show characteristic fluorescence of corresponding lanthanide metal ions in solid state at room temperature.

关键词： rare earth complexes luminescent property pyridine-2,5-dicarboxyllic acid,crystal structure

A polarized^(3)He system based on metastability-exchange optical pumping

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 72-81页

作者： Yuting Wang Liangyong Wu Kaiyuan Zhang mei Peng Siyu chen Haiyang yan State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Key Laboratory of Neutron Physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang 621900China

Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and *** this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)*** employed a Merritt coil system consisting of four square coils to furnish a uniform holding *** deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical *** the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the *** applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)*** have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and *** a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 ***,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 ***,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关键词： metastability exchange optical pumping polarized^(3)He magnetic resonance

燃烧-微库仑法汽油中有机氯含量测定方法的优化

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石化技术与应用 2024年第2期42卷 144-148页

作者：杨森张元广陆克平陈燕梅中国石化安庆分公司发展规划部安徽安庆246002 安庆师范大学化学化工学院安徽安庆246011

为了提高汽油中有机氯含量测定的准确度和精密度,基于燃烧-微库仑法,采用0.02 mol/L乙酸钠的水溶液作汽油无机氯萃取剂,优化了直接测定和总氯含量差减无机氯含量(差减法)测定汽油中有机氯含量的方法。结果表明:采用0.02 mol/L乙酸钠的... 详细信息

为了提高汽油中有机氯含量测定的准确度和精密度,基于燃烧-微库仑法,采用0.02 mol/L乙酸钠的水溶液作汽油无机氯萃取剂,优化了直接测定和总氯含量差减无机氯含量(差减法)测定汽油中有机氯含量的方法。结果表明:采用0.02 mol/L乙酸钠的水溶液取代水-乙醇(异丙醇)溶液作无机氯萃取剂,可取上层油相直接测定汽油有机氯含量;采用萃取剂内含0.10~0.20 mg/L无机氯盐的空白加标方法,解决现行差减法部分汽油中有机氯含量偏差大的问题;2种方法的测定结果相对偏差均不大于10%。

关键词：汽油无机氯有机氯燃烧-微库仑法萃取剂乙酸钠水溶液