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Production Chain Length and PPI-CPI Divergence:Analysis Based on the Global Input-output Price Model
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作者 Ni Hongfu Yan Bingqian Wu Liyuan 《China Economist》 2024年第3期49-69,共21页
Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production ... Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index. 展开更多
关键词 Global value chains length of production chains consumer price index producer price index
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Effects of quaternary ammonium chain length on the antibacterial and remineralizing effects of a calcium phosphate nanocomposite 被引量:15
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作者 Ke Zhang Lei Cheng +2 位作者 Michael D Weir Yu-Xing Bai Hockin HK Xu 《International Journal of Oral Science》 SCIE CAS CSCD 2016年第1期45-53,共9页
Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs... Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs) of 3-18 and determined their effects on a bonding agent. This study aimed to incorporate these QAMs into NACP nanocomposites for the first time to simultaneously endow the material with antibacterial and remineralizing capabilities and to investigate the effects of the CL on the mechanical and biofilm properties. Five QAMs were synthesized: DMAPM (CL3), DMAHM (CL6), DMADDM (CL12), DMAHDM (CL16), and DMAODM (CL18). Each QAM was incorporated into a composite containing 20% NACP and 50% glass fillers. A dental plaque microcosm biofilm model was used to evaluate the antibacterial activity. The flexural strength and elastic modulus of nanocomposites with QAMs matched those of a commercial control composite (n = 6; P 〉 0.1). Increasing the CL from 3 to 16 greatly enhanced the antibacterial activity of the NACP nanocomposite (P 〈 0.05); further increasing the CL to 18 decreased the antibacterial potency. The NACP nanocomposite with a CL of 16 exhibited biofilm metabolic activity and acid production that were 10-fold lesser than those of the control composite. The NACP nanocomposite with a CL of 16 produced 2-log decreases in the colony-forming units (CFU) of total microorganisms, total streptococci, and mutans streptococci. In conclusion, QAMs with CLs of 3-18 were synthesized and incorporated into an NACP nanocomposite for the first time to simultaneously endow the material with antibacterial and remineralization capabilities. Increasing the C/reduced the metabolic activity and acid production of biofilms and caused a 2-log decrease in CFU without compromising the mechanical properties. Nanocomposites exhibiting strong anti-biofilm activity, remineralization effects, and mechanical properties are promising materials for tooth restorations that inhibit caries. 展开更多
关键词 antibacterial nanocomposite calcium phosphate nanoparticles caries inhibition human saliva microcosm biofilm quaternary ammonium chain length
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Influence of Charge Density and Chain Length on the Interaction between Organic Anion and Montmorillonite 被引量:3
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作者 郑俊萍 LI Jian +1 位作者 HAO Hui YAO Kangde 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第1期6-11,共6页
Anionic surfantant sodium dodecyl sulfate (SDS), cationic surfactant cetyl trimethyl ammonium bromide (CTAB) and acrylic acid (AA) were introduced as molecular models to study the interaction between montmorillo... Anionic surfantant sodium dodecyl sulfate (SDS), cationic surfactant cetyl trimethyl ammonium bromide (CTAB) and acrylic acid (AA) were introduced as molecular models to study the interaction between montmorillonite and organic molecules with different charge or chain length. The compounds were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (13C NMR). The results show organic anion could interact strongly with montmorillonite, even the molecules could intercalate into the layers of MMT. 展开更多
关键词 chain length charge density INTERACTION montmoriUonitc.
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The Effect of the Chain Length on MMA Free Radicl Polymerization
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作者 Wang, M Mao, YG +3 位作者 Lu, YY Yang, RF Li, F Shen, JC 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期1041-1042,共2页
In the polymerization process of methyl methacrylate (MMA), the Arrhenius parameters (activation energy and frequency factor) of propagating reaction monotonically decrease with increasing monomer conversion. At the b... In the polymerization process of methyl methacrylate (MMA), the Arrhenius parameters (activation energy and frequency factor) of propagating reaction monotonically decrease with increasing monomer conversion. At the beginning and middle stage of the propagating reaction, the increase of radical chain length is the main reason of above mentioned change. And at the end stage, the sharp decrease of k(p) indicates that the activation energy is approximately incline to zero and the propagating reaction is controlled by molecular diffusion motion. 展开更多
关键词 MMA ARRHENIUS parameters propagating reaction radical chain length
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Effect of lengthening alkyl spacer on hydroformylation performance of tethered-phosphine modified Rh/SiO_2 catalyst 被引量:5
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作者 刘佳 严丽 +2 位作者 姜淼 李存耀 丁云杰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第2期268-272,共5页
Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-ph... Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-phospine,promoted the formation of active species and enhanced the activity of hydroformylation over other tethered-phosphine modified Rh/SiO2 catalysts. 展开更多
关键词 Tethered phosphine chain length RHODIUM Silica HYDRofORMYLATION
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Analysis on the anchor mechanism of the full length resin bolt
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作者 宋彦波 刘洪涛 《Journal of Coal Science & Engineering(China)》 2003年第1期79-81,共3页
The purpose of this paper is to reveal the stress distribution characteristic along the full length anchor bolt. Based on the mechanic model set up, the author calculated the anchor mechanism of the full length resin ... The purpose of this paper is to reveal the stress distribution characteristic along the full length anchor bolt. Based on the mechanic model set up, the author calculated the anchor mechanism of the full length resin rock bolt. The stress distribution characteristic is different according to different type of surrounding rock. The conclusion is important to optimize the roadway bolt support design. 展开更多
关键词 anchor mechanism full length resin rock bolt stress distribution characteristic bolt support design
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Regulation of the quantum barrier and carrier transport toward high-efficiency quasi-2D Dion-Jacobson tin perovskite solar cells
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作者 Huanhuan Yao Chang Shi +5 位作者 Tai Wu Shurong Wang Mingyu Yin Liming Ding Yong Hua Feng Hao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期200-207,I0005,共9页
Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural qu... Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites. 展开更多
关键词 chain lengths Organic spacers Quantum well Carrier transport Lattice distortion
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Research on the Correlation Between rs2110385 Polymorphisms of the Visfatin Gene and Nonproliferative Diabetic Retinopathy
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作者 Min Zhang Rong Li +2 位作者 Wei-guo Ma Xiao-hong Yin Ya Li 《Journal of Clinical and Nursing Research》 2024年第2期220-227,共8页
Objective:To investigate the association between rs2110385 polymorphisms of the visfatin gene and the risk of type 2 diabetic retinopathy(DR).Methods:172 Han subjects were selected from Xi’an Shaanxi Province;140 pat... Objective:To investigate the association between rs2110385 polymorphisms of the visfatin gene and the risk of type 2 diabetic retinopathy(DR).Methods:172 Han subjects were selected from Xi’an Shaanxi Province;140 patients with type 2 diabetes mellitus(T2DM)and 32 normal controls(NC)were selected from our hospital.Patients with diabetes were divided into a non-DR group(T2DM)(n=69)and a nonproliferative diabetic retinopathy Group(DR)(n=71)after dilated fundus photography and fundus fluorescein angiography.rs2110385/AluⅠgenotypes were detected by standardized polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP),and the differences in the detection rates of different genotypes in the above populations were compared.Results:1)The visfatin level in the DR Group was significantly higher than that in the NC and T2DM groups(P<0.05).2)The frequency of GG genotype and G allele of rs2110385 in the DR Group were higher than those in the T2DM and NC groups(80.3,69.6,50.0,86.6,79,65.6,P<0.05).3)There were significant differences in allele frequency and genotype frequency distribution of rs2110385 between the DR Group and the NC group(P<0.01).Conclusion:Visfatin increased in the nonproliferative diabetic retinopathy group and could be a potential indicator for the clinical prediction of DR.The G allele of the rs2110385 polymorphic site may be related to the risk of DR. 展开更多
关键词 VISFATIN Diabetic retinopathy Single nucleotide polymorphism Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP)
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Magnetization of a Gapped Spin 1/2 Antiferromagnetic Ising Chain near the Critical External Field
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作者 LIU Yi-Chang CHEN Yu-Guan LOU Ji-Zhong QIN Shao-Jin CHEN Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第12期733-736,共4页
We study the magnetization of gapped spin 1/2 XXZ Heisenberg Ising chains and calculate the scattering length among massive spinons. We obtain the magnetization close to the critical external magnetic field. The leadi... We study the magnetization of gapped spin 1/2 XXZ Heisenberg Ising chains and calculate the scattering length among massive spinons. We obtain the magnetization close to the critical external magnetic field. The leading correction term determined by the scattering length among massive spinons is given. Our results are in agreement with exact results and with experimental results. We show that the deviation from the massive free hard core boson picture can be accounted very well by the leading correction term due to the spinon-spinon interaction. We show that the deviation increases along with the increasing of the Ising term. 展开更多
关键词 magnetization XXZ SPIN 1/2 chain spinon-spinon scattering length
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The Effects of Apolipoprotein E Polymorphism on Serum Lipids, Lipoproteins and Apolipoproteins Variation 被引量:3
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作者 潘闽 朱健华 +2 位作者 袁瑾 王惠民 刘志华 《Journal of Nanjing Medical University》 2003年第4期196-200,共5页
Objective: To study the effects of Apolipoprotein E (ApoE) polymorphism onserum levels of lipids, lipoproteins and apolipoproteins. Methods: Fragments of ApoE gene forthex-on containing codon 112 and 158 polymorphic l... Objective: To study the effects of Apolipoprotein E (ApoE) polymorphism onserum levels of lipids, lipoproteins and apolipoproteins. Methods: Fragments of ApoE gene forthex-on containing codon 112 and 158 polymorphic locus were amplified by PCR, and then digested untilCfo I endonuclease. Genotypes and alleles frequencies of 168 healthy persons in Jiangsu area werecalculated. The effects of ApoE genotypes and alleles on serum lipids, lipoproteins andapolipoproteins variation were analyzed. Results: The effects of ApoE alleles on total cholesterol(TC), law density lipoprotein-cholesterol (LDL-C), ApoB was: along a decreasing gradientε_4>ε_3>ε_2. The effect of ε_4 allele was to increase serum levels of TC, LDL-C and ApoB, andthe ε_2 allele had an effect opposite to that of ε_4 allele. Conclusion: ApoE polymorphism is anindependent genetic factor on individual serum levels of lipids and apolipoproteins. 展开更多
关键词 Apolipoprotein E POLYMORPHISM polymerase chain reaction restrictionfragment length polymorphism
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Controlled Synthesis of PCL/PVP Copolymer by RAFT Method and Its HydrophUic Block-Dependent MiceUar Behaviors
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作者 李蕤 庞文民 +1 位作者 朱清仁 聂康明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第3期358-364,I0002,共8页
A range of poly(ε-caprolactone)/poly(N-vinyl-2-pyrrolidone) amphiphilic block copolymers with well-defined hydrophilic chain length were synthesized by the living/controlled reversible addition fragmentation chai... A range of poly(ε-caprolactone)/poly(N-vinyl-2-pyrrolidone) amphiphilic block copolymers with well-defined hydrophilic chain length were synthesized by the living/controlled reversible addition fragmentation chain transfer polymerization method. The composition and struc- ture of the targeted resultants were characterized with 1H NMR, 13C NMR, FT-IR spec- troscopy and gel permeation chromatography. The various block copolymers were success- fully employed to fabricate the spherical micelle with core-shell morphological structure. The poly(N-vinyl-2-pyrrolidone) block-dependent characteristics of the copolymeric micelles were investigated by fluorescence spectroscopy, dynamic light scattering, and transmission electron microscopy. The solubilization of the hydrophobic ibuprofen as a model drug in the micelle solution was also explored. It was found that the drug loading contents are related to the micellar morphology structure determined by hydrophilic chain length in the copolymer. 展开更多
关键词 RAFT polymerization Poly(N-vinyl-2-pyrrolidone) Core-shell structure Hydrophilic chain length Micellar behavior
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Studies on the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer
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作者 房殿春 罗元辉 +1 位作者 鲁荣 刘为纹 《World Journal of Gastroenterology》 SCIE CAS CSCD 1997年第1期24+22-23,22-23,共3页
AIM To study the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer.
关键词 Stomach neoplasms Genes ras Point mutation Polymerase chain reaction\ \ Polymorphism restriction fragment length Prognosis
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The relationship of Imp2 and DR3 genes with susceptibility to type Ⅰ diabetes mellitus in south China Han population 被引量:7
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作者 Ding HL Cheng H +3 位作者 Fu ZZ Deng QL Yan L Yan T 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第1期111-114,共4页
AIN To study the relationship of Imp2 and DR3genes with type Ⅰ diabetes mellitus.NETHODS Imp2 genotypes and DR3 wereidentified in 68 patients with type Ⅰ diabetesmellitus(Ⅰ-DM)and 71 healthy controls.Then,Ⅰ-DM pat... AIN To study the relationship of Imp2 and DR3genes with type Ⅰ diabetes mellitus.NETHODS Imp2 genotypes and DR3 wereidentified in 68 patients with type Ⅰ diabetesmellitus(Ⅰ-DM)and 71 healthy controls.Then,Ⅰ-DM patients and controls were respectivelyallocated into DR3-positive and DR3-negativegroups.The frequencies of Imp2 and DR3 genein random subjects,and Imp2 genotypes in DR3-matched subjects were compared between Ⅰ-DMpatients and controls.At the same time,Ⅰ-DMpatients were divided into 3 groups based on theonset age of diabetics:group A≤14 years,group B 15-30 years and group C≥31 years.RESULTS The frequency of DR3 in Ⅰ-DMpatients was significantly higher than that incontrols(47% vs 21%,P【0.005),and it wassignificantly higher in group A than that in groupB+C(70% vs 36%,x^2=7.07,P【0.01).Therewas a significant difference among groups withdifferent onset age of diabetics(x^2=8.19,rp=0.33,P【0.05).In random subjects,thefrequency of Imp2.R/R in Ⅰ-DM patients waslower(43% vs 61%,P【0.05)and Imp2.R/Hhigher(53% vs 28%,P【0.05)than that incontrols,and there was no significant differenceamong groups with different onset age ofdiabetics.In DR3-positive subjects,thefrequency of Imp2.R/R in Ⅰ-DM patients waslower(47% vs 87%,P【0.05)and Imp2-R/H higher(47% vs 13%,P【0.05)than that incontrols.In DR3-negative subjects,thefrequency of Imp2.R/H in Ⅰ-DM patients washigher than that in controls(58% vs 32%,P【0.01),but the frequency of Imp2-R/R and Imp2H/H was not significantly different betweenthese two groups.CONCLUSION DR3 gene may be one of thesusceptible genes of Ⅰ-DM,and significantlyrelated to the onset age of diabetics,and thepersons with DR3 may have an younger onsetage of diabeteS.The Imp2-R/R may be theprotective genotype of Ⅰ-DM,and Imp2-R/H thesusceptible genotype.These were not affectedby DR3 gene.Imp-2 genotypes were not relatedwith the onset age of diabetics. 展开更多
关键词 Subject headings diabetes MELLITUS Imp2 GENES DR3 GENES POLYMERASE chain reaction RESTRICTION FRAGMENT length polymorphism genetic SUSCEPTIBILITY
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Effect of nano-particle size on product distribution and kinetic parameters of Fe/Cu/La catalyst in Fischer-Tropsch synthesis 被引量:4
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作者 Ali Nakhaei Pour Mohammad Reza Housaindokht +1 位作者 Sayyed Faramarz Tayyari Jamshid Zarkesh 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第2期107-116,共10页
Effects of nano-particle size on hydrocarbon production rates and distributions for precipitated Fe/Cu/La catalysts in Fischer-Tropsch synthesis were investigated.Nano-structured iron catalyst was prepared by micro-em... Effects of nano-particle size on hydrocarbon production rates and distributions for precipitated Fe/Cu/La catalysts in Fischer-Tropsch synthesis were investigated.Nano-structured iron catalyst was prepared by micro-emulsion method.The concept of two superimposed AndersonSchulz-Flory (ASF) distributions has been applied for the representation of the effects of reaction conditions and nano-particles size on kinetics parameters and product distributions.These results reveal that by reducing the particle size of catalyst,the break in ASF distributions was decreased.Also useful different kinetics equations for synthesis of C3 to C9 and C10 to C22 were determined by using α1 and α2 chain growth probabilities. 展开更多
关键词 chain length distribution Fischer-Tropsch synthesis iron-based catalyst nano-particle size
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Optimization of nitrogen fertilization improves rice quality by affecting the structure and physicochemical properties of starch at high yield levels 被引量:6
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作者 ZHOU Tian-yang LI Zhi-kang +7 位作者 LI En-peng WANG Wei-lu YUAN Li-min ZHANG Hao LIU Li-jun WANG Zhi-qin GU Jun-fei YANG Jian-chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第6期1576-1592,共17页
A major challenge in modern rice production is to achieve the dual goals of high yield and good quality with low environmental costs.This study was designed to determine whether optimized nitrogen(N)fertilization coul... A major challenge in modern rice production is to achieve the dual goals of high yield and good quality with low environmental costs.This study was designed to determine whether optimized nitrogen(N)fertilization could fulfill these multiple goals.In two-year experiments,two high yielding‘super’rice cultivars were grown with different N fertilization management regimes,including zero N input,local farmers’practice(LFP)with heavy N inputs,and optimized N fertilization(ONF).In ONF,by reducing N input,increasing planting density,and optimizing the ratio of urea application at different stages,N use efficiency and the physicochemical and textural properties of milled rice were improved at higher yield levels.Compared with LFP,yield and partial factor productivity of applied N(PFP)under ONF were increased(on average)by 1.70 and 13.06%,respectively.ONF increased starch and amylose content,and significantly decreased protein content.The contents of the short chains of A chain(degree of polymerization(DP)6-12)and B1 chain(DP 13-25)of amylopectin were significantly increased under ONF,which resulted in a decrease in the stability of rice starch crystals.ONF increased viscosity values and improved the thermodynamic properties of starch,which resulted in better eating and cooking quality of the rice.Thus,ONF could substantially compensate the negative effects caused by N fertilizer and achieve the multiple goals of higher grain quality and nitrogen use efficiency(NUE)at high yield levels.These results will be useful for applications of high quality rice production at high yield levels. 展开更多
关键词 nitrogen fertilization rice starch starch structure physicochemical properties chain length distribution
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Studies on product distribution of alkali promoted iron catalyst in Fischer-Tropsch synthesis 被引量:2
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作者 Ali Nakhaei Pour Masoud Zare Yahya Zamani 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第1期31-34,共4页
The dependencies of hydrocarbon product distributions of alkali promoted iron catalyst in Fischer-Tropsch synthesis have been studied. The concept of two superimposed Anderson-Schulz-Flory distributions has been appli... The dependencies of hydrocarbon product distributions of alkali promoted iron catalyst in Fischer-Tropsch synthesis have been studied. The concept of two superimposed Anderson-Schulz-Flory distributions has been applied for the representation of the effects of Mg, La and Ca promoters on product distributions. The FTS performance of the catalysts was tested in a fixed bed reactor under the conditions 563 K, 1.7 MPa, H2/CO = 1 and space velocities 4.86 and 13.28 nl·h^-1·gFe^-1. The results indicate that appropriate amounts of these promoters enhance the break in ASF distributions in the order Ca 〉 Mg 〉 La because of the rising of the catalyst surface basicity. 展开更多
关键词 chain length distribution Fischer-Tropsch synthesis Fe catalyst
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An analytical analysis for the mechanical performance of fully-grouted rockbolts based on the exponential softening model 被引量:2
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作者 Zhongwen Yue Akang Li +1 位作者 Peng Wang Peng Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第5期981-995,共15页
This paper presented a novel bond-slip model to better reveal the mechanical behavior of the bolt-grout interface for fully-grouted rockbolts under tensile loads by considering the non-linear response in the softening... This paper presented a novel bond-slip model to better reveal the mechanical behavior of the bolt-grout interface for fully-grouted rockbolts under tensile loads by considering the non-linear response in the softening stage.The exponential decay function is adopted for describing the non-linear response in the softening stage.Based on the improved bond-slip model,the corresponding analytical solutions for the interfacial shear stress and the axial force of the bolt under different loading stages are solved.Then,the validity of this proposed model was verified by comparing with the experimental results.The results show that compared with the linear softening model,the proposed model is more suitable for predicting the mechanical performance of fully-grouted rockbolts.Finally,a series of parametric studies are conducted to explore the effect of model parameters on the mechanical properties of fully-grouted rockbolts.The results indicate that compared with the anchor length,the bolt diameter and the bond strength of the bolt-grout interface have a significance influence on the ultimate load of bolt,especially for the elastic and softening stage.Moreover,it can be found that using the linear softening model maybe overestimates the supporting performance of grouted bolt,resulting in an unsafe design for bolt. 展开更多
关键词 Fully-grouted rockbolts Non-linear response Bond-slip model anchor length Analytical solutions
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Increased sedimentation of a Pseudomonas–Saccharomyces microbial consortium producing medium chain length polyhydroxyalkanoates 被引量:1
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作者 Chang Liu Lin Qi +2 位作者 Songyuan Yang Yun He Xiaoqiang Jia 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第7期1659-1665,共7页
Concerns about feasibility,separability,settleability,efficiency once hampered studies on polyhydroxyalkanoates(PHAs)production,which mainly focused on single strain microorganism or activated sludge rather than artif... Concerns about feasibility,separability,settleability,efficiency once hampered studies on polyhydroxyalkanoates(PHAs)production,which mainly focused on single strain microorganism or activated sludge rather than artificial microbial consortia.Here,a medium chain length PHAs(mcl-PHAs)producing Pseudomonas-Saccharomyces consortium with xylose as the main substrate was studied.Mcl-PHAs accumulation increased from 12.69 mg·L^-1 to 152.3 mg·L^-1 without any optimization method.The presence of Saccharomyces cerevisiae,though in a relatively low concentration,improved the sedimentation of cell mass of the mixed culture by 60%.Reasons for better sedimentation of the consortium were complex:first,the length of Pseudomonas putida increased two to three times in the consortium;second,the positive surface charge of P.putida was neutralized by S.cerevisiae;third,the adhesion proteins on the surface of S.cerevisiae interacted with the P.putida. 展开更多
关键词 MEDIUM chain length POLYHYDROXYALKANOATES Pseudomonas–Saccharomyces consortium SEDIMENTATION XYLOSE
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The Impact of Climatic and Environmental Factors on n-Alkanes Indices in Southwestern Tibetan Plateau 被引量:2
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作者 LING Yuan ZHENG Mianping +3 位作者 WANG Shuxian SUN Qing XIE Bingjing ZHANG Chengjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第2期648-658,共11页
n-Alkanes are widely used in paleoenvironmental reconstructions.However,our understanding of changes in the distribution of n-alkanes with climatic and environmental factors remains unclear in arid/semi-arid regions.W... n-Alkanes are widely used in paleoenvironmental reconstructions.However,our understanding of changes in the distribution of n-alkanes with climatic and environmental factors remains unclear in arid/semi-arid regions.We sampled 26 surface sediments from three climatic zones across the southwestern Tibetan Plateau to evaluate the sensitivity of chain length distributions of n-alkanes to climatic and environmental parameters.Our observations demonstrate that average chain length(ACL),proportion of aquatic macrophyte(Paq),carbon preference index(CPI)and ratio of the contents of nC_(27)and nC_(31)(nC_(27)/nC_(31))are all sensitive to hydroclimatic conditions.In contrast to commonly-adopted assumptions,the correlations between these indices and hydrological parameters are not always good,which indicates that the interpretation of n-alkane indices is special on the southwestern Tibetan Plateau.These might be related to the vegetation characteristics and seasonality of biological activity,and need to be considered in paleoclimatic reconstruction.The impact of seasonal precipitation on n-alkanes indices was also evaluated. 展开更多
关键词 N-ALKANES average chain length CLIMATE environment Tibetan Plateau
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Analysis and Design of Trial Well Mooring in Deepwater of the South China Sea 被引量:2
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作者 Yongfeng Guo Shaojun Ji +3 位作者 Changquan Tang Jiansong Li Huiquan Zhong Ong Chin Yam Ian 《Journal of Marine Science and Application》 2012年第2期222-227,共6页
Mooring systems play an important role for semi-submersible rigs that drill in deepwater.A detailed analysis was carried out on the mooring of a semi-submersible rig that conducted a trial well drilling at a deepwater... Mooring systems play an important role for semi-submersible rigs that drill in deepwater.A detailed analysis was carried out on the mooring of a semi-submersible rig that conducted a trial well drilling at a deepwater location in the South China Sea in 2009.The rig was 30 years old and had a shallow platform with a designed maximum operating water depth of 457 m.Following the mooring analysis,a mooring design was given that requires upgrading of the rig’s original mooring system.The upgrade included several innovations,such as installing eight larger anchors,i.e.replacing the original anchors and inserting an additional 600 m of steel wires with the existing chains.All this was done to enhance the mooring capability of the rig in order for the rig to be held in position to conduct drilling at a water depth of 476 m.The overall duration of the drilling was 50 days and the upgraded mooring system proved to be efficient in achieving the goal of keeping the rig stationary while it was drilling the trial well in the South China Sea.This successful campaign demonstrates that an older semi-submersible rig can take on drilling in deep water after careful design and proper upgrading and modification to the original mooring system. 展开更多
关键词 offshore anchor operation MOORING chain wire CHASER drilling engineering semi submersible South China Sea anchor handling vessel(AHV)
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