The study involved the evaluation of the hydrocarbon potential of FORMAT Field, coastal swamp depobelt Niger delta, Nigeria to obtain a more efficient reservoir characterization and fluid properties identification. De...The study involved the evaluation of the hydrocarbon potential of FORMAT Field, coastal swamp depobelt Niger delta, Nigeria to obtain a more efficient reservoir characterization and fluid properties identification. Despite advances in seismic data interpretation using traditional 3D seismic data interpretation, obtaining adequate reservoir characteristics at the finest level had proved very challenging with often disappointing results. A method that integrates the amplitude variation with offfset (AVO) analysis is hereby proposed to better illuminate the reservoir. The Hampson Russell 10.3 was used to integrate and study the available seismic and well data. The reservoir of interest was delineated using the available suite of petrophysical data. This was marked by low gamma ray, high resistivity, and low acoustic impedance between a true subsea vertical depth (TVDss) range of 10,350 - 10,450 ft. The AVO fluid substitution yielded a decrease in the density values of pure gas (2.3 - 1.6 g/cc), pure oil (2.3 - 1.8 g/cc) while the Poisson pure brine increased (2.3 to 2.8 g/cc). Result from FORMAT 26 plots yielded a negative intercept and negative gradient at the top and a positive intercept and positive gradient at the Base which conforms to Class III AVO anomaly. FORMAT 30 plots yielded a negative intercept and positive gradient at the top and a positive intercept and negative gradient at the Base which conforms to class IV AVO anomaly. AVO attribute volume slices decreased in the Poisson ratio (0.96 to - 1.0) indicating that the reservoir contains hydrocarbon. The s-wave reflectivity and the product of the intercept and gradient further clarified that there was a Class 3 gas sand in the reservoir and the possibility of a Class 4 gas sand anomaly in that same reservoir.展开更多
Quantifying surface cracks in alpine meadows is a prerequisite and a key aspect in the study of grassland crack development.Crack characterization indices are crucial for the quantitative characterization of complex c...Quantifying surface cracks in alpine meadows is a prerequisite and a key aspect in the study of grassland crack development.Crack characterization indices are crucial for the quantitative characterization of complex cracks,serving as vital factors in assessing the degree of cracking and the development morphology.So far,research on evaluating the degree of grassland degradation through crack characterization indices is rare,especially the quantitative analysis of the development of surface cracks in alpine meadows is relatively scarce.Therefore,based on the phenomenon of surface cracking during the degradation of alpine meadows in some regions of the Qinghai-Tibet Plateau,we selected the alpine meadow in the Huangcheng Mongolian Township,Menyuan Hui Autonomous County,Qinghai Province,China as the study area,used unmanned aerial vehicle(UAV)sensing technology to acquire low-altitude images of alpine meadow surface cracks at different degrees of degradation(light,medium,and heavy degradation),and analyzed the representative metrics characterizing the degree of crack development by interpreting the crack length,length density,branch angle,and burrow(rat hole)distribution density and combining them with in situ crack width and depth measurements.Finally,the correlations between the crack characterization indices and the soil and root parameters of sample plots at different degrees of degradation in the study area were analyzed using the grey relation analysis.The results revealed that with the increase of degradation,the physical and chemical properties of soil and the mechanical properties of root-soil composite changed significantly,the vegetation coverage reduced,and the root system aggregated in the surface layer of alpine meadow.As the degree of degradation increased,the fracture morphology developed from"linear"to"dendritic",and eventually to a complex and irregular"polygonal"pattern.The crack length,width,depth,and length density were identified as the crack characterization indices via analysis of variance.The results of grey relation analysis also revealed that the crack length,width,depth,and length density were all highly correlated with root length density,and as the degradation of alpine meadows intensified,the underground biomass increased dramatically,forming a dense layer of grass felt,which has a significant impact on the formation and expansion of cracks.展开更多
Ensemble-based analyses are useful to compare equiprobable scenarios of the reservoir models.However,they require a large suite of reservoir models to cover high uncertainty in heterogeneous and complex reservoir mode...Ensemble-based analyses are useful to compare equiprobable scenarios of the reservoir models.However,they require a large suite of reservoir models to cover high uncertainty in heterogeneous and complex reservoir models.For stable convergence in ensemble Kalman filter(EnKF),increasing ensemble size can be one of the solutions,but it causes high computational cost in large-scale reservoir systems.In this paper,we propose a preprocessing of good initial model selection to reduce the ensemble size,and then,EnKF is utilized to predict production performances stochastically.In the model selection scheme,representative models are chosen by using principal component analysis(PCA)and clustering analysis.The dimension of initial models is reduced using PCA,and the reduced models are grouped by clustering.Then,we choose and simulate representative models from the cluster groups to compare errors of production predictions with historical observation data.One representative model with the minimum error is considered as the best model,and we use the ensemble members near the best model in the cluster plane for applying EnKF.We demonstrate the proposed scheme for two 3D models that EnKF provides reliable assimilation results with much reduced computation time.展开更多
Several new MEMS Inertial Measurement Unit(IMU) sensor products have been released recently with improved performance,which have the potential to support much higher precision applications.New MEMS IMUs include the Na...Several new MEMS Inertial Measurement Unit(IMU) sensor products have been released recently with improved performance,which have the potential to support much higher precision applications.New MEMS IMUs include the NavChip from InterSense,the Nav440 from Crossbow,the Landmark30/40 from GTI,the SDI500 from Systron Donner.Since they are new in the market,currently there is limited information about their error characterization which however is important for the construction of proper error models for their integration with other sensors such as GPS.This paper will investigate the error characterization of two new MEMS IMU sensors,namely the NavChip and Nav440,using Allan variance technique.In addition to identifying different error terms,different stochastic error modeling methods,such as Gauss-Markov(GM) and Autoregressive(AR) processes,will also be investigated to assess the MEMS IMU sensor biases.Investigation to integrate new MEMS IMU sensors with Precise Point Positioning(PPP) will also be conducted to address the re-convergence issues.展开更多
Distributions of pubescences on leaf blade and hull in japonica rice were observed under an optical microscope. Numbers of leaf and hull pubescences in P1, P2, F1, B1, B2 and F2 generations were investigated in three ...Distributions of pubescences on leaf blade and hull in japonica rice were observed under an optical microscope. Numbers of leaf and hull pubescences in P1, P2, F1, B1, B2 and F2 generations were investigated in three combinations of japonica rice (Sidao 10A/Wuyujing 3R, Wuyujing 3A/Sidao 10R and Liuyan 189A/HR-122), and genetic analysis for these two traits were conducted by using the joint analysis method of P1, P2, F1, B1, B2 and F2 generations with the mixed major gene plus polygene inheritance models. Leaf pubescences characterized by swollen base and fine tip distributed regularly on the boundary between dark green stripe and light green stripe of leaf blade. Hull pubescences with various lengths distributed irregularly on the whole hull. Numbers of leaf pubescences in the reciprocal combinations of Sidao 10A/Wuyujing 3R and Wuyujing 3A/Sidao 10R and numbers of hull pubescences in all the three combinations were controlled by one pair of additive major genes plus additive-dominant polygenes. In the combination of Liuyan 189A/HR-122, number of leaf pubescences was controlled by one pair of additive-dominant major genes plus additive-dominant polygenes. Both numbers of leaf and hull pubescences were mainly governed by major genes.展开更多
Taking Wuhan,Nanjing and Guangzhou as examples and using Logistic model and Moran index,this paper made a quantitative analysis on bribery characterization of developers in land market. It found that( i) bribery behav...Taking Wuhan,Nanjing and Guangzhou as examples and using Logistic model and Moran index,this paper made a quantitative analysis on bribery characterization of developers in land market. It found that( i) bribery behavior of developers is promoted by supply and demands;( ii) bribery behavior of developers takes on regional agglomeration and difference. It reached following conclusions:( i) under the influence of macro factors and micro factors,bribery behavior of developers is rational selection after full consideration of institutional environment and corporate strength,and is passive to a certain extent;( ii) bribery behavior of developers has certain spatial correlation,and the high-high correlation characteristic is most significant.展开更多
Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar d...Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar distance(D):2.0?4.0cm and current density(J):100?400A/m2.The electrolytic products obtained under optimum conditions of c=0.04mol/L,t=78°C,D=2.0cm and J=100A/m2were further isolated by vacuum distillation under5kPa.The product was characterized byFourier transform infrared(FT-IR)spectra,nuclear magnetic resonance(NMR)spectra.The results indicated that the product washafnium ethoxide.ICP analysis suggested that the content of hafnium ethoxide in the final product exceeded99.997%.Thermalproperties of the product were analyzed by TG/DTG.The vaporization enthalpy of hafnium ethoxide was found to be79.1kJ/mol.The result confirmed that hafnium ethoxide was suitable for the preparation of hafnium oxide by atomic layer deposition.展开更多
Long noncoding RNAs(lncRNAs)are widely present in different species and play critical roles in response to abiotic stresses.However,the functions of lncRNAs in Chinese cabbage under heat stress remain unknown.Here,we ...Long noncoding RNAs(lncRNAs)are widely present in different species and play critical roles in response to abiotic stresses.However,the functions of lncRNAs in Chinese cabbage under heat stress remain unknown.Here,we first conducted a global comparative analysis of 247,242 lncRNAs among 37 species.The results indicated that lncRNAs were poorly conserved among different species,and only 960 lncRNAs were homologous to 524 miRNA precursors.We then carried out lncRNA sequencing for a genome-wide analysis of lncRNAs and their target genes in Chinese cabbage at different stages of heat treatment.In total,18,253 lncRNAs were identified,of which 1229 differentially expressed(DE)lncRNAs were characterized as being heat-responsive.The ceRNA network revealed that 38 lncRNAs,16 miRNAs,and 167 mRNAs were involved in the heat response in Chinese cabbage.Combined analysis of the cis-and trans-regulated genes indicated that the targets of DE lncRNAs were significantly enriched in the“protein processing in endoplasmic reticulum”and“plant hormone signal transduction”pathways.Furthermore,the majority of HSP and PYL genes involved in these two pathways exhibited similar expression patterns and responded to heat stress rapidly.Based on the networks of DE lncRNA-mRNAs,29 and 22 lncRNAs were found to interact with HSP and PYL genes,respectively.Finally,the expression of several critical lncRNAs and their targets was verified by qRT-PCR.Overall,we conducted a comparative analysis of lncRNAs among 37 species and performed a comprehensive analysis of lncRNAs in Chinese cabbage.Our findings expand the knowledge of lncRNAs involved in the heat stress response in Chinese cabbage,and the identified lncRNAs provide an abundance of resources for future comparative and functional studies.展开更多
Aluminum-activated malate transporters(ALMT)are widely involved in plant growth and metabolic processes,including adaptation to acid soils,guard cell regulation,anion homeostasis,and seed development.Although ALMT gen...Aluminum-activated malate transporters(ALMT)are widely involved in plant growth and metabolic processes,including adaptation to acid soils,guard cell regulation,anion homeostasis,and seed development.Although ALMT genes have been identified in Arabidopsis,wheat,barley,and Lotus japonicus,little is known about its presence in Gossypium hirsutum L.In this study,ALMT gene recognition in diploid and tetraploid cotton were done using bioinformatics analysis that examined correlation between homology and evolution.Differentially regulated ALMT genetic profile in G.hirsutum was examined,using RNA sequencing and qRT-PCR,during six fiber developmental time-points,namely 5 d,7 d,10 d,15 d,20 d,and 25 d.We detected 36 ALMT genes in G.hirsutum,which were subsequently annotated and divided into seven sub-categories.Among these ALMT genes,34 had uneven distribution across 14/26 chromosomes.Conserved domains and gene structure analysis indicated that ALMT genes were highly conserved and composed of exons and introns.The GhALMT gene expression profile at different DPA(days post anthesis)in different varieties of G.hirsutum is indicative of a crucial role of ALMT genes in fiber development in G.hirsutum.This study provides basis for advancements in the cloning and functional enhancements of ALMT genes in enhancing fiber development and augmenting high quality crop production.展开更多
Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering construction.The deformation characteristics of broken gangue under the bearing compression play a ...Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering construction.The deformation characteristics of broken gangue under the bearing compression play a decisive role in the firmness,stability and safety of these structures(buildings),and the meso-fabric change of broken gangue under the bearing compression significantly affects its macro deformation.In this study,the transparent characterization and quantitative analysis of 3D fabric of broken gangue under the bearing compression were performed through CT scanning test,image processing and 3D reconstruction technology,and the influence mechanism of internal fabric of broken gangue on its macro deformation was revealed.The results show that:In the loading stage of 0–2 MPa,the sharp corners,thin edges on the blocks and the bar-shaped and blade-shaped blocks with poor regularity are broken first under the bearing compression;in the loading stage of 2–8 MPa,a large number of larger particles in the sample are crushed in the mode of fragmentation;in the loading stage of 8–10 MPa,the breakage degree of samples is relieved.The axial displacement of the block inside the sample occurs,as well as the lateral displacement of the block converging to the central axis of the sample.In the rapid deformation stage,the macro deformation of the broken gangue is mainly caused by the rearrangement and adjustment of the block structure and the breakage of the block;in the slow deformation stage,it is mainly caused by the breakage of the block;in the stable deformation stage,it is mainly caused by the optimization and adjustment of the bearing skeleton in the sample.展开更多
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent and prevalent nitrosamine procarcinogen found in cigarette smoke. The aim of this work is to study alterations in peroxiredoxin (Prx) expression...4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent and prevalent nitrosamine procarcinogen found in cigarette smoke. The aim of this work is to study alterations in peroxiredoxin (Prx) expression induced by NNK during carcinogenesis. Characterization of Prx genes from hamster was performed using bioinformatics.展开更多
The full-length cDNA encoding Larval serum protein 2 (LSp-2) in the onion maggot,Delia antiqua, was cloned and sequenced by rapid ampli?cation of cDNA ends methods. The result showed that the cDNA was 2203 bp long and...The full-length cDNA encoding Larval serum protein 2 (LSp-2) in the onion maggot,Delia antiqua, was cloned and sequenced by rapid ampli?cation of cDNA ends methods. The result showed that the cDNA was 2203 bp long and the open reading frame (ORF) of 2106 bp encoded 701 amino acid with a calculated molecular weight of 80.5 kDa and an isoelectric point of 5.87. The onion maggot LSp-2 shows highest homology (83%) to that ofCalliphora vicinaat amino acid level. Its signal peptides, domains and structures were predicted and analyzed by using bioinformatic methods. The amino acid sequence of LSP-2 suggests that it would be a typical hexamerin.展开更多
Cracks and ruptures always occur during wire drawing process of 42% nickel-iron expansive alloy. In order to study the reasons of these phenomena,a method of metallographic observation in combination with sample elect...Cracks and ruptures always occur during wire drawing process of 42% nickel-iron expansive alloy. In order to study the reasons of these phenomena,a method of metallographic observation in combination with sample electrolysis was used to characterize the non-metallic inclusions in the alloy wire. The results indicate that the inclusions in the alloy are oxidation products during the process of melting. There are single or complex phase inclusions composed of elements such as Al,Si,Ca,Ti,Fe,and O2. Among them,the macro-inclusions are TiO2 compound inclusions formed by the adhesion of Al and Si oxides on them. These inclusions are fragile ones with a low strain rate,as well as a rather high hardness,so that they are the main reason that leads to the surface cracks and ruptures in the alloy wires. The analysis has educed that the key point to enhance the product quality is to promote the cleanliness of the melt,control the types and quantity of non-metal inclusions in the alloy.展开更多
In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, ...In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, internode length, the transverse and longitudinal diameters of the largest leaf, single fruit weight, flesh thickness and soluble solid content of 41 cultivars were measured for conducting diversity, correlation and cluster analysis. The results revealed that the pumpkin cultivars showed large variations in fruit stem length, single fruit weight, fruit length and flesh thickness, but small variations in initial flowering date. Significant, even highly significant correlations were found among the tested traits. Cluster analysis demonstrated that the 41 old Cucurbita moschata cultivars were divided into three groups, of which multiple traits of Group 1 were better than those in the other two groups. High similarities existed in three groups and the cultivars in each group. This research provided basis for selecting excellent traits and parents for the breeding of hybrids.展开更多
[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 ...[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character (containing 18 variables) were verified, including yield characters (5 variables), caulis characters (6 variables), branch characters (3 variables) and pod characters (3 variables). [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits.展开更多
Lawrence's novels are perhaps the most powerful exploration in the genre in English of family,class,sexuality and relationships in youth and early adulthood.Since the birth of this novel,varies comments on it were...Lawrence's novels are perhaps the most powerful exploration in the genre in English of family,class,sexuality and relationships in youth and early adulthood.Since the birth of this novel,varies comments on it were continuous.This analysis briefly introduces the personality of the main character-Paul Morel by means of specific description in the story.展开更多
INTRODUCTION In recent years, with the gradual improvement of road construction, the rapid increase of the number of motor vehicles, vehicle emissions and the current poor vehicle performance, poor vehicle maintenance...INTRODUCTION In recent years, with the gradual improvement of road construction, the rapid increase of the number of motor vehicles, vehicle emissions and the current poor vehicle performance, poor vehicle maintenance, higher emission factor and so on, air pollution caused by the traffic issues becomes the focus of people attention. The harmful substances are gradually accumulated to atmosphere particles surrounding roads due to dust particles (soil dusts, road dusts, construction dusts), coal emissions, industrial emissions, vehicle emissions, biomass burning, secondary particles, which has a certain harmful influence to the atmosphere, soil and plants surrounding roads.展开更多
A lot of experimental methods have been brought forth to assess the dynamic character of the arc welding power source, but up to now, this issue has not been solved very well. In this paper, based on the fuzzy logic r...A lot of experimental methods have been brought forth to assess the dynamic character of the arc welding power source, but up to now, this issue has not been solved very well. In this paper, based on the fuzzy logic reasoning method, a dynamic character assessing model for the arc welding power source was established and used to analyze the dynamic character of the welding power source. Three different types of welding machine have been tested, and the characteristic information of the electrical signals such as re-striking arc voltage, low welding current and so on of the welding process were extracted accurately by using a self-developed welding dynamic arc wavelet analyzer. The experimental results indicate that this model can be used as a new assessing method for the dynamic character of the arc welding power source.展开更多
[Objectives]To establish a method for quality analysis of Medicine Pileostegia tomentella Hand.-Mazz.[Methods]According to the testing method of Chinese Pharmacopoeia(2020 Edition),the water content,total ash and alco...[Objectives]To establish a method for quality analysis of Medicine Pileostegia tomentella Hand.-Mazz.[Methods]According to the testing method of Chinese Pharmacopoeia(2020 Edition),the water content,total ash and alcohol-soluble extract of P.tomentella Hand.-Mazz.were determined.[Results]10 batches of P.tomentella Hand.-Mazz.from different habitats and in different collection time in Guangxi all had the same plant morphology and medicinal properties.The experimental results showed that the water content was 7.92%-10.35%,the total ash content was 5.53%-6.62%,the acid-insoluble ash content was 0.59%-0.76%,and the extract content was 11.63%-16.12%.[Conclusions]The identification method in this study can be used for the quality analysis of P.tomentella Hand.-Mazz.,and the experimental results can provide a scientific basis for the development and utilization of P.tomentella Hand.-Mazz.and the establishment of its quality standard.展开更多
Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup compone...Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results.展开更多
文摘The study involved the evaluation of the hydrocarbon potential of FORMAT Field, coastal swamp depobelt Niger delta, Nigeria to obtain a more efficient reservoir characterization and fluid properties identification. Despite advances in seismic data interpretation using traditional 3D seismic data interpretation, obtaining adequate reservoir characteristics at the finest level had proved very challenging with often disappointing results. A method that integrates the amplitude variation with offfset (AVO) analysis is hereby proposed to better illuminate the reservoir. The Hampson Russell 10.3 was used to integrate and study the available seismic and well data. The reservoir of interest was delineated using the available suite of petrophysical data. This was marked by low gamma ray, high resistivity, and low acoustic impedance between a true subsea vertical depth (TVDss) range of 10,350 - 10,450 ft. The AVO fluid substitution yielded a decrease in the density values of pure gas (2.3 - 1.6 g/cc), pure oil (2.3 - 1.8 g/cc) while the Poisson pure brine increased (2.3 to 2.8 g/cc). Result from FORMAT 26 plots yielded a negative intercept and negative gradient at the top and a positive intercept and positive gradient at the Base which conforms to Class III AVO anomaly. FORMAT 30 plots yielded a negative intercept and positive gradient at the top and a positive intercept and negative gradient at the Base which conforms to class IV AVO anomaly. AVO attribute volume slices decreased in the Poisson ratio (0.96 to - 1.0) indicating that the reservoir contains hydrocarbon. The s-wave reflectivity and the product of the intercept and gradient further clarified that there was a Class 3 gas sand in the reservoir and the possibility of a Class 4 gas sand anomaly in that same reservoir.
基金This study was funded by the National Natural Science Foundation of China(42062019,42002283)the Project of Qinghai Science&Technology Department(2021-ZJ-927).
文摘Quantifying surface cracks in alpine meadows is a prerequisite and a key aspect in the study of grassland crack development.Crack characterization indices are crucial for the quantitative characterization of complex cracks,serving as vital factors in assessing the degree of cracking and the development morphology.So far,research on evaluating the degree of grassland degradation through crack characterization indices is rare,especially the quantitative analysis of the development of surface cracks in alpine meadows is relatively scarce.Therefore,based on the phenomenon of surface cracking during the degradation of alpine meadows in some regions of the Qinghai-Tibet Plateau,we selected the alpine meadow in the Huangcheng Mongolian Township,Menyuan Hui Autonomous County,Qinghai Province,China as the study area,used unmanned aerial vehicle(UAV)sensing technology to acquire low-altitude images of alpine meadow surface cracks at different degrees of degradation(light,medium,and heavy degradation),and analyzed the representative metrics characterizing the degree of crack development by interpreting the crack length,length density,branch angle,and burrow(rat hole)distribution density and combining them with in situ crack width and depth measurements.Finally,the correlations between the crack characterization indices and the soil and root parameters of sample plots at different degrees of degradation in the study area were analyzed using the grey relation analysis.The results revealed that with the increase of degradation,the physical and chemical properties of soil and the mechanical properties of root-soil composite changed significantly,the vegetation coverage reduced,and the root system aggregated in the surface layer of alpine meadow.As the degree of degradation increased,the fracture morphology developed from"linear"to"dendritic",and eventually to a complex and irregular"polygonal"pattern.The crack length,width,depth,and length density were identified as the crack characterization indices via analysis of variance.The results of grey relation analysis also revealed that the crack length,width,depth,and length density were all highly correlated with root length density,and as the degradation of alpine meadows intensified,the underground biomass increased dramatically,forming a dense layer of grass felt,which has a significant impact on the formation and expansion of cracks.
基金supported by The Ministry of Trade,Industry,and Energy(20172510102090,20142520100440,20162010201980)Global PhD Fellowship Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2015H1A2A1030756)supported by the National Research Foundation of Korea(NRF)Grant(No.2018R1C1B5045260).
文摘Ensemble-based analyses are useful to compare equiprobable scenarios of the reservoir models.However,they require a large suite of reservoir models to cover high uncertainty in heterogeneous and complex reservoir models.For stable convergence in ensemble Kalman filter(EnKF),increasing ensemble size can be one of the solutions,but it causes high computational cost in large-scale reservoir systems.In this paper,we propose a preprocessing of good initial model selection to reduce the ensemble size,and then,EnKF is utilized to predict production performances stochastically.In the model selection scheme,representative models are chosen by using principal component analysis(PCA)and clustering analysis.The dimension of initial models is reduced using PCA,and the reduced models are grouped by clustering.Then,we choose and simulate representative models from the cluster groups to compare errors of production predictions with historical observation data.One representative model with the minimum error is considered as the best model,and we use the ensemble members near the best model in the cluster plane for applying EnKF.We demonstrate the proposed scheme for two 3D models that EnKF provides reliable assimilation results with much reduced computation time.
基金Excellent talents Program of Liaoning Province(LR2011007)supported by the Natural Sciences and Engineering Research Council(NSERC)of Canada and Tecterra as well as Program for Liaoning Excellent Talents in University,China~~
文摘Several new MEMS Inertial Measurement Unit(IMU) sensor products have been released recently with improved performance,which have the potential to support much higher precision applications.New MEMS IMUs include the NavChip from InterSense,the Nav440 from Crossbow,the Landmark30/40 from GTI,the SDI500 from Systron Donner.Since they are new in the market,currently there is limited information about their error characterization which however is important for the construction of proper error models for their integration with other sensors such as GPS.This paper will investigate the error characterization of two new MEMS IMU sensors,namely the NavChip and Nav440,using Allan variance technique.In addition to identifying different error terms,different stochastic error modeling methods,such as Gauss-Markov(GM) and Autoregressive(AR) processes,will also be investigated to assess the MEMS IMU sensor biases.Investigation to integrate new MEMS IMU sensors with Precise Point Positioning(PPP) will also be conducted to address the re-convergence issues.
文摘Distributions of pubescences on leaf blade and hull in japonica rice were observed under an optical microscope. Numbers of leaf and hull pubescences in P1, P2, F1, B1, B2 and F2 generations were investigated in three combinations of japonica rice (Sidao 10A/Wuyujing 3R, Wuyujing 3A/Sidao 10R and Liuyan 189A/HR-122), and genetic analysis for these two traits were conducted by using the joint analysis method of P1, P2, F1, B1, B2 and F2 generations with the mixed major gene plus polygene inheritance models. Leaf pubescences characterized by swollen base and fine tip distributed regularly on the boundary between dark green stripe and light green stripe of leaf blade. Hull pubescences with various lengths distributed irregularly on the whole hull. Numbers of leaf pubescences in the reciprocal combinations of Sidao 10A/Wuyujing 3R and Wuyujing 3A/Sidao 10R and numbers of hull pubescences in all the three combinations were controlled by one pair of additive major genes plus additive-dominant polygenes. In the combination of Liuyan 189A/HR-122, number of leaf pubescences was controlled by one pair of additive-dominant major genes plus additive-dominant polygenes. Both numbers of leaf and hull pubescences were mainly governed by major genes.
基金Supported by National Social Science Foundation of China"Empirical Study of Corruption Governance in Real Estate"(14BGL106)
文摘Taking Wuhan,Nanjing and Guangzhou as examples and using Logistic model and Moran index,this paper made a quantitative analysis on bribery characterization of developers in land market. It found that( i) bribery behavior of developers is promoted by supply and demands;( ii) bribery behavior of developers takes on regional agglomeration and difference. It reached following conclusions:( i) under the influence of macro factors and micro factors,bribery behavior of developers is rational selection after full consideration of institutional environment and corporate strength,and is passive to a certain extent;( ii) bribery behavior of developers has certain spatial correlation,and the high-high correlation characteristic is most significant.
基金Project(51374254) supported by the National Natural Science Foundation of China
文摘Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar distance(D):2.0?4.0cm and current density(J):100?400A/m2.The electrolytic products obtained under optimum conditions of c=0.04mol/L,t=78°C,D=2.0cm and J=100A/m2were further isolated by vacuum distillation under5kPa.The product was characterized byFourier transform infrared(FT-IR)spectra,nuclear magnetic resonance(NMR)spectra.The results indicated that the product washafnium ethoxide.ICP analysis suggested that the content of hafnium ethoxide in the final product exceeded99.997%.Thermalproperties of the product were analyzed by TG/DTG.The vaporization enthalpy of hafnium ethoxide was found to be79.1kJ/mol.The result confirmed that hafnium ethoxide was suitable for the preparation of hafnium oxide by atomic layer deposition.
基金the National Natural Science Foundation of China(31801856 to X.S.)the Hebei Province Higher Education Youth Talents Program(BJ2018016 to X.S.)+1 种基金the China Postdoctoral Science Foundation(2020M673188 to X.S.)the Natural Science Foundation of Hebei(C2017209103 to X.S.).
文摘Long noncoding RNAs(lncRNAs)are widely present in different species and play critical roles in response to abiotic stresses.However,the functions of lncRNAs in Chinese cabbage under heat stress remain unknown.Here,we first conducted a global comparative analysis of 247,242 lncRNAs among 37 species.The results indicated that lncRNAs were poorly conserved among different species,and only 960 lncRNAs were homologous to 524 miRNA precursors.We then carried out lncRNA sequencing for a genome-wide analysis of lncRNAs and their target genes in Chinese cabbage at different stages of heat treatment.In total,18,253 lncRNAs were identified,of which 1229 differentially expressed(DE)lncRNAs were characterized as being heat-responsive.The ceRNA network revealed that 38 lncRNAs,16 miRNAs,and 167 mRNAs were involved in the heat response in Chinese cabbage.Combined analysis of the cis-and trans-regulated genes indicated that the targets of DE lncRNAs were significantly enriched in the“protein processing in endoplasmic reticulum”and“plant hormone signal transduction”pathways.Furthermore,the majority of HSP and PYL genes involved in these two pathways exhibited similar expression patterns and responded to heat stress rapidly.Based on the networks of DE lncRNA-mRNAs,29 and 22 lncRNAs were found to interact with HSP and PYL genes,respectively.Finally,the expression of several critical lncRNAs and their targets was verified by qRT-PCR.Overall,we conducted a comparative analysis of lncRNAs among 37 species and performed a comprehensive analysis of lncRNAs in Chinese cabbage.Our findings expand the knowledge of lncRNAs involved in the heat stress response in Chinese cabbage,and the identified lncRNAs provide an abundance of resources for future comparative and functional studies.
基金This study was funded by the National Natural Science Foundation of China(U1804103,31101188)Sponsored by State Key Laboratory of Cotton Biology Open Fund(CB2020A10).
文摘Aluminum-activated malate transporters(ALMT)are widely involved in plant growth and metabolic processes,including adaptation to acid soils,guard cell regulation,anion homeostasis,and seed development.Although ALMT genes have been identified in Arabidopsis,wheat,barley,and Lotus japonicus,little is known about its presence in Gossypium hirsutum L.In this study,ALMT gene recognition in diploid and tetraploid cotton were done using bioinformatics analysis that examined correlation between homology and evolution.Differentially regulated ALMT genetic profile in G.hirsutum was examined,using RNA sequencing and qRT-PCR,during six fiber developmental time-points,namely 5 d,7 d,10 d,15 d,20 d,and 25 d.We detected 36 ALMT genes in G.hirsutum,which were subsequently annotated and divided into seven sub-categories.Among these ALMT genes,34 had uneven distribution across 14/26 chromosomes.Conserved domains and gene structure analysis indicated that ALMT genes were highly conserved and composed of exons and introns.The GhALMT gene expression profile at different DPA(days post anthesis)in different varieties of G.hirsutum is indicative of a crucial role of ALMT genes in fiber development in G.hirsutum.This study provides basis for advancements in the cloning and functional enhancements of ALMT genes in enhancing fiber development and augmenting high quality crop production.
基金supported by the National Natural Science Foundation of China(Nos.52104103,52022107,52174128)the Natural Science Foundation of Jiangsu Province(Nos.BK20210499,BK20190031)。
文摘Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering construction.The deformation characteristics of broken gangue under the bearing compression play a decisive role in the firmness,stability and safety of these structures(buildings),and the meso-fabric change of broken gangue under the bearing compression significantly affects its macro deformation.In this study,the transparent characterization and quantitative analysis of 3D fabric of broken gangue under the bearing compression were performed through CT scanning test,image processing and 3D reconstruction technology,and the influence mechanism of internal fabric of broken gangue on its macro deformation was revealed.The results show that:In the loading stage of 0–2 MPa,the sharp corners,thin edges on the blocks and the bar-shaped and blade-shaped blocks with poor regularity are broken first under the bearing compression;in the loading stage of 2–8 MPa,a large number of larger particles in the sample are crushed in the mode of fragmentation;in the loading stage of 8–10 MPa,the breakage degree of samples is relieved.The axial displacement of the block inside the sample occurs,as well as the lateral displacement of the block converging to the central axis of the sample.In the rapid deformation stage,the macro deformation of the broken gangue is mainly caused by the rearrangement and adjustment of the block structure and the breakage of the block;in the slow deformation stage,it is mainly caused by the breakage of the block;in the stable deformation stage,it is mainly caused by the optimization and adjustment of the bearing skeleton in the sample.
基金supported by Doctor Foundation of Zhengzhou University of Light IndustryScientific and technological research projects in Zhengzhou City(141PPTGG399)Scientific and technological research projects in Henan province
文摘4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent and prevalent nitrosamine procarcinogen found in cigarette smoke. The aim of this work is to study alterations in peroxiredoxin (Prx) expression induced by NNK during carcinogenesis. Characterization of Prx genes from hamster was performed using bioinformatics.
文摘The full-length cDNA encoding Larval serum protein 2 (LSp-2) in the onion maggot,Delia antiqua, was cloned and sequenced by rapid ampli?cation of cDNA ends methods. The result showed that the cDNA was 2203 bp long and the open reading frame (ORF) of 2106 bp encoded 701 amino acid with a calculated molecular weight of 80.5 kDa and an isoelectric point of 5.87. The onion maggot LSp-2 shows highest homology (83%) to that ofCalliphora vicinaat amino acid level. Its signal peptides, domains and structures were predicted and analyzed by using bioinformatic methods. The amino acid sequence of LSP-2 suggests that it would be a typical hexamerin.
基金Project( ZGS064-A52-036-04) supported by Gansu Provincial Scientific Key Scientific and Technological ProjectProject(2006-05) supported by Difficult Bidding Project of Jinchuan Group Ltd.
文摘Cracks and ruptures always occur during wire drawing process of 42% nickel-iron expansive alloy. In order to study the reasons of these phenomena,a method of metallographic observation in combination with sample electrolysis was used to characterize the non-metallic inclusions in the alloy wire. The results indicate that the inclusions in the alloy are oxidation products during the process of melting. There are single or complex phase inclusions composed of elements such as Al,Si,Ca,Ti,Fe,and O2. Among them,the macro-inclusions are TiO2 compound inclusions formed by the adhesion of Al and Si oxides on them. These inclusions are fragile ones with a low strain rate,as well as a rather high hardness,so that they are the main reason that leads to the surface cracks and ruptures in the alloy wires. The analysis has educed that the key point to enhance the product quality is to promote the cleanliness of the melt,control the types and quantity of non-metal inclusions in the alloy.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture of China(201303112)the 12th National Five-year Plan for Science and Technology Program of Rural Areas(2012BAD02B03-17)~~
文摘In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, internode length, the transverse and longitudinal diameters of the largest leaf, single fruit weight, flesh thickness and soluble solid content of 41 cultivars were measured for conducting diversity, correlation and cluster analysis. The results revealed that the pumpkin cultivars showed large variations in fruit stem length, single fruit weight, fruit length and flesh thickness, but small variations in initial flowering date. Significant, even highly significant correlations were found among the tested traits. Cluster analysis demonstrated that the 41 old Cucurbita moschata cultivars were divided into three groups, of which multiple traits of Group 1 were better than those in the other two groups. High similarities existed in three groups and the cultivars in each group. This research provided basis for selecting excellent traits and parents for the breeding of hybrids.
基金Supported by National Natural Science Foundation(30760122)National High-Tech Research and Development Program(863Program)(2009AA101105)+1 种基金Faculty Construction of 211 Project(SZTD-211-02)Project of Introducing Advanced Agricultural Science and Technology of Ministry of Agriculture(948Program)(2010-Z54)~~
文摘[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character (containing 18 variables) were verified, including yield characters (5 variables), caulis characters (6 variables), branch characters (3 variables) and pod characters (3 variables). [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits.
文摘Lawrence's novels are perhaps the most powerful exploration in the genre in English of family,class,sexuality and relationships in youth and early adulthood.Since the birth of this novel,varies comments on it were continuous.This analysis briefly introduces the personality of the main character-Paul Morel by means of specific description in the story.
基金financially supported by National Major Scientific Instrument Equipment Development Special(2011YQ060111)
文摘INTRODUCTION In recent years, with the gradual improvement of road construction, the rapid increase of the number of motor vehicles, vehicle emissions and the current poor vehicle performance, poor vehicle maintenance, higher emission factor and so on, air pollution caused by the traffic issues becomes the focus of people attention. The harmful substances are gradually accumulated to atmosphere particles surrounding roads due to dust particles (soil dusts, road dusts, construction dusts), coal emissions, industrial emissions, vehicle emissions, biomass burning, secondary particles, which has a certain harmful influence to the atmosphere, soil and plants surrounding roads.
基金This work is supported by Guangdong Natural Science Fund (04020100)
文摘A lot of experimental methods have been brought forth to assess the dynamic character of the arc welding power source, but up to now, this issue has not been solved very well. In this paper, based on the fuzzy logic reasoning method, a dynamic character assessing model for the arc welding power source was established and used to analyze the dynamic character of the welding power source. Three different types of welding machine have been tested, and the characteristic information of the electrical signals such as re-striking arc voltage, low welding current and so on of the welding process were extracted accurately by using a self-developed welding dynamic arc wavelet analyzer. The experimental results indicate that this model can be used as a new assessing method for the dynamic character of the arc welding power source.
基金Supported by 2022 Guangxi University Young and Middle-aged Teachers Basic Scientific Research Ability Improvement Project(2022KY0307)Key R&D Project of Guangxi Science and Technology Department(GuiKe AB21196057)+5 种基金General Project of Guangxi University of Chinese Medicine in 2022(2022MS038)Self-Raised Scientific Research Fund Project of Guangxi Zhuang Autonomous Region Administration of Traditional Chinese Medicine(GXZYA20220171)Key Project of Guangxi International Zhuang Medicine Hospital(GZ2021010)Zhuang Medicine Study,A Key Discipline of Traditional Chinese Medicine(Ethnopharmacology)in National Administration of Traditional Chinese Medicine during the 12 th Five-Year PlanHigh-level Talent Cultivation Innovation Team Fund Project of Guangxi University of Chinese Medicine(2022A008)Talent Training Project of"Young Talent Project"in Guangxi International Zhuang Medicine Hospital(2022001).
文摘[Objectives]To establish a method for quality analysis of Medicine Pileostegia tomentella Hand.-Mazz.[Methods]According to the testing method of Chinese Pharmacopoeia(2020 Edition),the water content,total ash and alcohol-soluble extract of P.tomentella Hand.-Mazz.were determined.[Results]10 batches of P.tomentella Hand.-Mazz.from different habitats and in different collection time in Guangxi all had the same plant morphology and medicinal properties.The experimental results showed that the water content was 7.92%-10.35%,the total ash content was 5.53%-6.62%,the acid-insoluble ash content was 0.59%-0.76%,and the extract content was 11.63%-16.12%.[Conclusions]The identification method in this study can be used for the quality analysis of P.tomentella Hand.-Mazz.,and the experimental results can provide a scientific basis for the development and utilization of P.tomentella Hand.-Mazz.and the establishment of its quality standard.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61574019,61674018 and 61674020the Fund of State Key Laboratory of Information Photonics and Optical Communicationsthe Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No 20130005130001
文摘Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results.