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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 Pinus yunnanensis seedlings DROUGHT Non-structural carbohydrates c N P stoichiometric characteristics
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Triple Notched Band Characteristics UWB Antenna Using C-Shaped Slots and Slot-Type Capacitively-Loaded Loop (CLL)
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作者 Ahmed Zitouni Noureddine Boukli-Hacene 《Journal of Electromagnetic Analysis and Applications》 2013年第8期342-345,共4页
Ultra wide bands antennas with notched bands characteristics have recently been considered for efficient communication between devices. In this paper, a compact ultra-wideband antenna (UWB) for UWB applications with t... Ultra wide bands antennas with notched bands characteristics have recently been considered for efficient communication between devices. In this paper, a compact ultra-wideband antenna (UWB) for UWB applications with triple bandnotched characteristics is presented. The proposed antenna consists of a square patch with four truncated corners and a partial ground plane with a rectangular slit. The operation bandwidth of the designed antenna is from 2.66 GHz to more than 13.5 GHz. Band-notched characteristics of antenna to reject the frequency band of 3.18 - 3.59 GHz and 4.70 - 5.88 GHz, is realized by inserting two C-shaped slots in the patch, the third band of 9.54 - 12.22 GHz is achieved by slottype capacitively-loaded loop (CLL) inserted in the patch near the feed line. Details of the proposed antenna design and simulated results are presented and discussed. 展开更多
关键词 Microstrip ANTENNA Ultra-Wideband ANTENNA UWB c-Shaped Slot capacitively-Loaded LOOP (cLL) Three-Band Notched characteristics
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Calculation of Aerodynamic Characteristics of Hypersonic Vehicles Based on the Surface Element Method 被引量:1
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作者 Tianqiang Huang Guoyi He Qi Wang 《Advances in Aerospace Science and Technology》 2022年第2期112-122,共11页
A program for calculating the aerodynamic properties of hypersonic vehicles based on the surface element method was developed using the general-purpose programming language C++. The calculated values of lift coefficie... A program for calculating the aerodynamic properties of hypersonic vehicles based on the surface element method was developed using the general-purpose programming language C++. The calculated values of lift coefficients, drag coefficients, and surface pressure coefficients are discussed with the results of wind tunnel experiments using the HL-20 lift body and the NASA hypersonic aircraft STS Columbia OV-102 as research subjects. Finally, the results of the experimental and wind tunnel studies of the aerodynamic characteristics of the HL-20 lift body at an altitude of 65 km and Mach numbers of 6 and 10 Ma are discussed. The maximum error in the aerodynamic characteristics at 6 Ma does not exceed 3%, consistent with the results. The maximum error at 10 Ma occurs in the 11° - 14° angle of attack and does not exceed 10%, which is still within the error tolerance. The STS results for NASA’s hypersonic aircraft were also tested using this procedure. Experimental aerodynamic data for the Colombian OV-102 aircraft. The results show that the program takes only 10 minutes to calculate the results, with no more than 2% error from the wind tunnel experimental results. 展开更多
关键词 Surface Element Method Hypersonic Vehicle c++ Aerodynamic characteristics Engineering calculations
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Brief Analyses of Some Contradictory Characteristics of the Language Applied in Business Correspondence
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作者 WANG Hong-ling(English Department of Huaian College of Information Technology,Huaian,Jiangsu 223003) 《广西大学学报(哲学社会科学版)》 2007年第S2期187-189,共3页
Business correspondence are the indispensable tool in the practical process of business communication and interchange.Especially,as the communicated body of information,their language possesses specific characteristic... Business correspondence are the indispensable tool in the practical process of business communication and interchange.Especially,as the communicated body of information,their language possesses specific characteristics.Rooted from the "Politeness Principle" and the "Cooperative Principle",the most distinctive epitome of it is the seven "C" principles.Based on the discussion of the seven "C" principles,this paper devotes itself to the analyses of the contradictory characteristics which occur frequently in the concrete business contexts,and then to examine the causes of these features.Ultimately,it will suggest more flexible and more widened perspective towards the creation of business correspondence and the language applied in them. 展开更多
关键词 business cORRESPONDENcE SEVEN "c" PRINcIPLES cONTRADIcTORY characteristics
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Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Seeds under Different Temperatures 被引量:2
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作者 刘金花 李佳 张永清 《Agricultural Science & Technology》 CAS 2010年第9期213-216,共4页
[Objective] To study the germination characteristics and secondary metabolism of Scutellaria baicalensis Georgi seeds under different temperatures.[Method]The activities of superoxide dismutase(SOD)and peroxidase(... [Objective] To study the germination characteristics and secondary metabolism of Scutellaria baicalensis Georgi seeds under different temperatures.[Method]The activities of superoxide dismutase(SOD)and peroxidase(POD)were determined with lactoflavine-NBT method and guaiacol-colorimetry assay,respectively.The catalase(CAT),ascorbate peroxidase(APX),phenylalanine ammonia-lyase(PAL)and cinnamic acid 4-Hydroxylase(C4H)were determined with ultraviolet spectrophotometry.The secondary metabolites were detected by High Performance Liquid Chromatography(HPLC).[Result]The germination percentage,germination potentiality and germination index were seriously affected by low or high temperature.The proper germination temperature was 20-25 ℃.The activities of SOD,POD and CAT were significantly decreased as comparison to suitable temperature.The activities of PAL and C4H were also significantly decreased as comparision to suitable temperature which was accordance to the secondary metabolites.There was a positive correlation between the flavonoids content and the PAL and C4H activity(r=0.956,r=0.951,P0.05).[Conclusion]The quality of the skullcaps could be improved by improving the activity of PAL and C4H.The proper temperature for the seed germination and the formation of secondary metabolites was 20 ℃. 展开更多
关键词 Germination characteristics Antioxidant enzyme PAL c4H Secondary metabolites
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Comparison of the clinical characteristics and survival between Uyghur patients with hepatitis virus-related and non-B, non-C hepatocellular carcinoma in Xinjiang, China 被引量:10
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作者 Lei Xiao Rui-Li Zhang +4 位作者 Hua Zhang Aisiker Tulahong Yue-Fen Zhang Hao Wen Yong-Xing Bao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第3期279-287,共9页
Objective: To compare the clinical characteristics and prognosis between hepatitis virus-related hepatocellular carcinoma(viral HCC) and non-B, non-C HCC(NBC-HCC) among Uyghur patients in Xinjiang province, China... Objective: To compare the clinical characteristics and prognosis between hepatitis virus-related hepatocellular carcinoma(viral HCC) and non-B, non-C HCC(NBC-HCC) among Uyghur patients in Xinjiang province, China. Methods: Between 01/01/2000 and 31/12/2012, 319 Uyghur HCC patients were treated at the Cancer Centre of The First Affiliated Hospital of Xinjiang Medical University. The data for the patients were obtained from a retrospective review of the patients' medical records. A total of 18 patients were excluded from the study because of incomplete information. The patients were classified into two groups: viral HCC and NBC-HCC. The clinical characteristics and prognostic factors were statistically analysed.Results: For all 301 patients, gender(P=0.000), area of residence(P=0.002), diabetes mellitus(P=0.009), BMI(P=0.000), cirrhosis(P=0.000), tumour stage(P=0.004), Child-Pugh class(P=0.000), the TBIL level(P=0.000), and the alpha-fetoprotein(AFP) level(P=0.000) were significantly different between the NBC-HCC and viral HCC groups. The NBC-HCC patients tended to be diagnosed at advanced stages; however, the NBC-HCC patients exhibited lower Child-Pugh scores than the viral HCC patients. In all patients examined, the 0.5-, 1-, 3- and 5-year overall survival(OS) rates were 35.6%, 20.3%, 12.6% and 4.5%, respectively. No significant difference in OS was observed between the two groups(P=0.124). Cox multivariate analysis revealed that age(RR =1.539, P=0.001), TNM stage(RR =12.708, P=0.000), portal vein tumour thrombus(PVTT)(RR =2.003, P=0.000), Child-Pugh class(RR =1.715, P=0.000), and TACE + radiotherapy/RFA(RR =0.567, P=0.000) were significant independent prognostic factors for HCC patients. Conclusions: The clinical characteristics differ between Uyghur patients with NBC-HCC and viral HCC. HCC in the Xinjiang region displays specific regional characteristics. Age, TNM stage, PVTT, Child-Pugh class and TACE + radiotherapy/RFA are significant risk factors that influence patient survival. 展开更多
关键词 Hepatocellular carcinoma (Hcc Uyghur people non-B non-c Hcc (NBc-Hcc hepatitis virusrelated Hcc (viral Hcc clinical characteristics
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The electrical characteristics of a 4H-silicon carbide metal-insulator-semiconductor structure with Al_2O_3 as the gate dielectric 被引量:1
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作者 刘莉 杨银堂 马晓华 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期366-372,共7页
A 4H-silicon carbide metal-insulator-semiconductor structure with ultra-thin Al2O3 as the gate dielectric, deposited by atomic layer deposition on tile epitaxial layer of a 4H-SiC (0001) 80N-/N+ substrate, has been... A 4H-silicon carbide metal-insulator-semiconductor structure with ultra-thin Al2O3 as the gate dielectric, deposited by atomic layer deposition on tile epitaxial layer of a 4H-SiC (0001) 80N-/N+ substrate, has been fabricated. The experimental results indicate that the prepared ultra-thin Al2O3 gate dielectric exhibits good physical and electrical characteristics, including a high breakdown electrical field of 25 MV/cm, excellent interface properties (1 × 10^14 cm^-2) and low gate-leakage current (IG = 1 × 10^-3 A/cm 2@Eox = 8 MV/cm). Analysis of the current conduction mecha- nism on the deposited Al2O3 gate dielectric was also systematically performed. The confirmed conduction mechanisms consisted of Fowler-Nordheim (FN) tuaneling, the Frenkel-Poole mechanism, direct tunneling and Schottky emission, and the dominant current conduction mechanism depends on the applied electrical field. When the gate leakage current mechanism is dominated by FN tunneling, the barrier height of SiC/Al2O3 is 1.4 eV, which can meet the requirements of silicon carbide metal-insulator-semiconductor transistor devices. 展开更多
关键词 AL2O3 4H-silicon carbide metal-insulator-semiconductor capacitor gate leakage current c-V characteristics
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Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Under Osmotic Stress with PEG
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作者 Jinhua LIU Qian LIU +1 位作者 Jia LI Yongqing ZHANG 《Agricultural Biotechnology》 CAS 2019年第1期57-60,共4页
[Objectives]This study was conducted to study the Germination characteristics and secondary metabolism regulation of Scutellaria baicalensis Georgi under osmotic stress.[Methods]The activity of praline,soluble sugar a... [Objectives]This study was conducted to study the Germination characteristics and secondary metabolism regulation of Scutellaria baicalensis Georgi under osmotic stress.[Methods]The activity of praline,soluble sugar and protein was detected with ultraviolet spectrophotometry.The activity of phenylalanine ammonia-lyase(PAL)and cinnamic acid 4-hydroxylase(C_4H)was determined with ultraviolet spectrophotometry.The secondary metabolites were detected by high performance liquid chromatography(HPLC).[Results]The germination percentage,germination potentiality and germination index decreased at first and increased subsequently along with the enhancement of PEG concentration.The praline content,the soluble sugar content and the soluble protein content in S.baicalensis seedlings increased along with the enhancement of PEG concentration and the differences from the CK were significant(P<0.05).The PAL and C_4H in S.baicalensis seedlings decreased after osmotic stress and the differences from the CK were significant(P<0.05).The results indicate that,the scutellarin,baicalin,wogonoside,baicalein,wogonin and oroxylinA contents decreased after osmotic stress and the differences from the CK were significant(P<0.05).[Conclusions]The quality of the skullcaps could be improved by improving the activity of PAL and C_4H. 展开更多
关键词 GERMINATION characteristics PAL c 4H SEcONDARY METABOLITES
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A Novel Technique for Determination of Flow Characteristics of Blast Furnace Slag
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作者 Supratik Dash Nachiketa Mohanty +1 位作者 Upendra K. Mohanty Smarajit Sarkar 《Open Journal of Metal》 2012年第2期42-47,共6页
A study of flow characteristics of blast furnace slag helps determine its softening and flow (liquid-mobility) temperatures. The slag with a narrow difference between the two temperatures is termed a “Short Slag”. I... A study of flow characteristics of blast furnace slag helps determine its softening and flow (liquid-mobility) temperatures. The slag with a narrow difference between the two temperatures is termed a “Short Slag”. Its formation ensures higher rates of slag-metal reactions with the trickle of the slag soon after its formation exposing fresh mass for faster reactions, the trickling slag, creating fresh interfaces facilitating slag-metal exchanges. In the present work, a novel technique is adopted to determine the flow characteristics of blast furnace slag obtained from different industrial blast furnaces. It is seen that the results so obtained agree very closely with the values obtained from adopting conventional methods of determining the liquidus temperature using “slag atlas”. It is observed that under the range of compositions studied a high C/S ratio combined with a high MgO content in the slag is beneficial to the B.F. process as it renders a “short slag”. 展开更多
关键词 Slag-Metal REAcTIONS characteristic TEMPERATURES HOT METAL Quality c/S Ratio Short SLAG
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All Fiber-optic Fluorescent Spectral Measurement and Analysis on Alga Chla/c Characteristics
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作者 ZHANG Shu-qing (School of Electr. Eng., Yanshan University,Qinhuangdao 066004,CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第2期120-124,共5页
The fluorescent principle used for measuring alga characteristic parameters and the optimum structure design of the instrument are discussed. The fluorescent spectrum of Chla/c and the time-resolved different spectrum... The fluorescent principle used for measuring alga characteristic parameters and the optimum structure design of the instrument are discussed. The fluorescent spectrum of Chla/c and the time-resolved different spectrum ΔA(λ,t) are given. The research provides an effective method for considering the density and the classification of algae, which will be helpful to monitor sea pollution. 展开更多
关键词 Fluorescent measurement Fiber optic transmission Alga chla/c characteristic spectra
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Clinical characteristics and current management of hepatitis B and C in China 被引量:8
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作者 Yong-Tao Sun Yue-Xin Zhang +7 位作者 Hong Tang Qing Mao Xiao-Zhong Wang Ling-Yi Zhang Hong Chen Ying-Na Zhong Shu-Mei Lin Da-Zhi Zhang 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13582-13590,共9页
AIM: To describe a population of outpatients in China infected by hepatitis B virus (HBV) and/or hepatitis C virus (HCV), and assess their current management status. METHODS: A multicenter, cross-sectional study of HB... AIM: To describe a population of outpatients in China infected by hepatitis B virus (HBV) and/or hepatitis C virus (HCV), and assess their current management status. METHODS: A multicenter, cross-sectional study of HBV- and/or HCV-infected patients was conducted from August to November, 2011 in western China. Patients >= 18 years of age with HBV and/or HCV infections who visited outpatient departments at 10 hospitals were evaluated, whether treated or not. Data were collected on the day of visit from medical records and patient interviews. RESULTS: A total 4010 outpatients were analyzed, including 2562 HBV- infected and 1406 HCV-infected and 42 HBV/HCV co-infected patients. The median duration of documented infection was 7.5 years in HBV- infected and 1.8 years in HCV-infected patients. Cirrhosis was the most frequent hepatic complication (12.2%), appearing in one-third of patients within 3 years prior to or at diagnosis. The HCV genotype was determined in only 10% of HCV-infected patients. Biopsy data were only available for 54 patients (1.3%). Antiviral medications had been received by 58.2% of patients with HBV infection and 66.6% with HCV infection. Nucleos(t) ide analogs were the major antiviral medications prescribed for HBV- infected patients (most commonly adefovir dipivoxil and lamivudine). Ribavirin + pegylated interferon was prescribed for two-thirds of HCV-infected patients. In the previous 12 mo, around one-fifth patients had been hospitalized due to HBV or HCV infection. CONCLUSION: This observational, real-life study has identified some gaps between clinical practice and guideline recommendations in China. To achieve better health outcomes, several improvements, such as disease monitoring and optimizing antiviral regimens, should be made to improve disease management. (C) 2014 Baishideng Publishing Group Inc. All rights reserved. 展开更多
关键词 Hepatitis B Hepatitis c clinical characteristics TREATMENT
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Stability analysis of intermittently jointed rock slopes based on the stepped failure mode
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作者 LI Dejian FU Junwen +4 位作者 LI Hekai CHENG Xiao ZHAO Lianheng ZHANG Yingbin PENG Xinyan 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1019-1035,共17页
In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock slopes.Especially for intermitt... In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock slopes.Especially for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure regions.Based on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(F_(s))of intermittently jointed rock slopes.The sequential quadratic programming method is used to obtain the optimal upper-bound solution for F_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also explored.The reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of F_(s)with each key parameter are obtained.The results show that F_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas F_(s)changes nonlinearly with H and L.In particular,with the increase in Kφand Kc,Fs increases by approximately 52.78%and 171.02%on average,respectively.For rock bridge tensile failure,F_(s) shows a nonlinearly positive correlation withφr,cr,Kφand Kc.In particular,with the increase in Kφand Kc,Fs increases by approximately 13%and 61.69%on average,respectively.Fs decreases rapidly with increasing slope gradientβand decreasing dimensionless parameterμ.When Kφand Kc are both less than 1.0,the stepped sliding surface occurs more easily than the plane failure surface,especially in the case of tensile failure of the rock bridge.In addition,rock slopes with higher strength parameters,taller heights,and greater weakening coefficients are prone to rock bridge tension failure with lower Fs,and more attention should be given to the occurrence of such accidents in actual engineering. 展开更多
关键词 Jointed rock slopes Stepped sliding failure Weakening characteristics Modified M‒c failure criterion
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Geochemical Characteristics of C_5–C_7 Light Hydrocarbons in Gas Hydrates from the Permafrost Region of Qilian Mountains 被引量:2
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作者 ZHANG Min KONG Ting HE Yu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2283-2284,共2页
As an important part of gas hydrates, light hydrocarbons (LHs), especially C5 to C7 hydrocarbons with various monomer compounds, provide a wide variety of geological and geochemical information, which have received ... As an important part of gas hydrates, light hydrocarbons (LHs), especially C5 to C7 hydrocarbons with various monomer compounds, provide a wide variety of geological and geochemical information, which have received much attention from organic geochemists and petroleum geologists. 展开更多
关键词 Geochemical characteristics of c5 c7 Light Hydrocarbons in Gas Hydrates from the Permafrost Region of Qilian Mountains
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A Study on the Characteristics of Carbon-Related Spectral Lines from a Laser-Induced Fly Ash Plasma 被引量:3
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作者 潘刚 陆继东 +3 位作者 董美蓉 姚顺春 谢子鑫 樊炬 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第8期625-631,共7页
A 1064 nm Nd:YAG laser was used to of the spectral lines measured from the laserablated ablate fly ash samples. The characteristics fly ash plasmas are presented with special attention to atomic and molecular carbon ... A 1064 nm Nd:YAG laser was used to of the spectral lines measured from the laserablated ablate fly ash samples. The characteristics fly ash plasmas are presented with special attention to atomic and molecular carbon emission. It is shown that the intensity of the atomic line C I 192.9 nm is weak and the shot-to-shot intensity is fluctuant. The carbon atomic line C I 247.7 nm is relatively intensive and stable, however it is seriously interfered with by Fe I 247.8 nm. The intensity of the CN molecular line is close to that of C I 247.7 nm and the CN line is stable and less interfered with. The comparison of molecular CN emission under different conditions (air, Ar and N2) shows that the CN lines detected from the plasmas formed in an atmospheric environment are correlated with the reaction of carbon atoms in the plasma with the nitrogen in air, which indicates that the CN line is also important in pulsed laser ablation fly ash plasmas and this information can be incorporated in the detection of unburned carbon content in fly ash. Finally, a calibration curve is established with a correlation coefficient R2 of 0.999, using C I 247.7 nm and the CN molecular line as associated variables. In addition, accuracy is improved to a certain extent. 展开更多
关键词 characteristics fly ash LIBS c-related spectra
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Identification of HPLC Characteristic Chromatograms of Phenylethanoid Glycosides and Iridoid Glycosides in Herba Cistanche of Different Origins 被引量:1
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作者 Xiongmei HUANG Yan HUANG +3 位作者 Xinwei NONG Minling WEI Hongyan WEI Hisayoshi NORIMOTO 《Medicinal Plant》 CAS 2020年第5期41-43,48,共4页
[Objectives]This study aimed to establish a quality evaluation method for Herba Cistanche based on the HPLC characteristic chromatograms of the phenylethanoid glycosides and iridoid glycosides,and compare the HPLC cha... [Objectives]This study aimed to establish a quality evaluation method for Herba Cistanche based on the HPLC characteristic chromatograms of the phenylethanoid glycosides and iridoid glycosides,and compare the HPLC characteristic chromatograms of different origins of Herba Cistanche.[Methods]The chromatographic conditions used were as follows:column,Agilent ZORBAX Eclipse Plus C18 column(4.6 mm×250 mm,5μm);gradient elution,acetonitrile-0.1%phosphoric acid aqueous solution;flow rate,1.0 mL/min;detection wavelength,240 nm;column temperature,30℃.[Results]Cistanche tubulosa(Schenk)Wight showed 9 characteristic peaks,Cistanche deserticola Y.C.Ma showed 10 characteristic peaks,Cistanche salsa(C.A.Mey.)G.Beck showed 7 characteristic peaks,and Cistanche sinensis G.Beck showed 4 characteristic peaks.Peak 6 was echinacoside,peak 7 was verbascoside,peak 8 was tubuloside A,peak 9 was isoacteoside and peak 10 was cistanoside A.The characteristic chromatograms of the four different origins of Herba Cistanche were significantly different.[Conclusions]This characteristic chromatogram method has good reproducibility and can be used to distinguish 4 different origins of Herba Cistanche,C.deserticola Y.C.Ma,C.tubulosa(Schenk)Wight,C.sinensis G.Beck and C.salsa(C.A.Mey.)G.Beck. 展开更多
关键词 cistanche deserticola Y.c.Ma cistanche tubulosa(Schenk)Wight cistanche sinensis G.Beck cistanche salsa(c.A.Mey.)G.Beck characteristic chromatogram HPLc
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Characterization of humic acids extracted from the sediments of the various rivers and lakes in China 被引量:36
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作者 HE Mengchang SHI Yehong LIN Chunye 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第11期1294-1299,共6页
The humic acids (HAs) isolated from the sediments of the various rivers,lakes,and reservoirs in China were studied using elemental analyzer,fourier transform infrared (FT-IR),and CP/MAS 13C nuclear magnetic resonance ... The humic acids (HAs) isolated from the sediments of the various rivers,lakes,and reservoirs in China were studied using elemental analyzer,fourier transform infrared (FT-IR),and CP/MAS 13C nuclear magnetic resonance (NMR) spectroscopy.The results showed that the HAs were characterized by some common chemical and physicochemical properties,but they also pose some differences in the C-containing functional groups.The C/N,C/H,O/C,and O/H ratios differ widely for the various HAs,showing that the elemental comp... 展开更多
关键词 cP/MAS 13c NMR spectroscopy elemental analysis fourier transform infrared spectroscopy humic acids surficial sediment structural characteristics
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Comprehensive evaluation of 20 pomegranate(Punica granatum L.) cultivars in China 被引量:3
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作者 CHEN Yan-hui GAO Hui-fang +6 位作者 WANG Sa LIU Xian-yan HU Qing-xia JIAN Zai-hai WAN Ran SONG Jin-hui SHI Jiang-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第2期434-445,共12页
Recent investigations on pomegranate products have significantly increased and successfully drawn consumers’ attention to nutritional and medicinal values, promoting the pomegranate industry’s development worldwide.... Recent investigations on pomegranate products have significantly increased and successfully drawn consumers’ attention to nutritional and medicinal values, promoting the pomegranate industry’s development worldwide. However, little information on pomegranates grown in China is available. Morphological and chemical characterizations of fruits and arils from 20 pomegranate cultivars in six regions of China were investigated. Combined with overall scores by principal component analysis, ‘Yushiliu No. 1’, ‘Taishanhong No. 2’, ‘Tunisia’ and ‘Mollar’ were promising cultivars, and Chinese researchers bred the first two. It was surprising that ‘Mollar’ had bigger fruit size and more aril moisture grown in China than in Spain. Cultivars with higher anthocyanin content in arils were ‘Turkey’, ‘Moyu’ and ‘Red Angel’, which might be used as the source of natural red food colourants. While red husk ‘Hongruyi’ and ‘Hongshuangxi’ with higher vitamin C, aril moisture and lower titratable acid in arils, might also be promising cultivars for further various utilization. Furthermore, the comparison of ‘Tunisia’ fruits from four regions revealed that cultivation locations had more influence on fruit traits than genotypes. Maturity index classification was established for Chinese pomegranate cultivars. Therefore, the results would provide a valuable guide for agricultural cultivation, industrial utilization, and breeding. 展开更多
关键词 Punica granatum L. fruit morphological characteristics aril assessment husk colour vitamin c anthocyanin content
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2 cm以上的C-TI-RADS 3类甲状腺结节的临床特点分析
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作者 唐艺峰 王龙龙 +4 位作者 刘益豪 张逸菲 李红强 马润声 殷德涛 《西安交通大学学报(医学版)》 CSCD 北大核心 2024年第1期74-79,共6页
目的统计2 cm以上的中国版甲状腺影像报告及数据系统(C-TI-RADS)3类甲状腺结节的临床特点,并探究其与性别、结节成分、对侧是否有癌、是否弥漫性回声改变、甲状腺过氧化物酶抗体(thyroid peroxidase antibody,TPOAB)、甲状腺球蛋白抗体(... 目的统计2 cm以上的中国版甲状腺影像报告及数据系统(C-TI-RADS)3类甲状腺结节的临床特点,并探究其与性别、结节成分、对侧是否有癌、是否弥漫性回声改变、甲状腺过氧化物酶抗体(thyroid peroxidase antibody,TPOAB)、甲状腺球蛋白抗体(anti-thyroglobulin antibodies,TGAB)等的相关性。方法回顾性分析2022年9月-2023年3月我科收治的甲状腺超声C-TI-RADS 3类且最大直径≥2 cm的94例甲状腺结节患者(均接受细胞病理和/或组织病理检查)的临床病理学信息。统计TBSⅠ类、良性、低风险肿瘤、恶性的比例,并比较性别、结节成分、对侧是否有癌、是否弥漫性回声改变、TPOAB、TGAB等临床特点在良性、低风险肿瘤、恶性三组中的比例有无统计学差异。结果排除7例TBSⅠ类患者,87例结节病理明确患者中,良性72例(细胞学38例、组织学34例)、低风险肿瘤5例(细胞学2例、组织学3例)、恶性10例(PTC 8例、FTC 1例、MTC 1例)。不同病理类型之间,结节成分(囊实性/实性)组间差异具有显著性,差异有统计学意义(χ^(2)=10.369,P=0.006);性别、是否弥漫性回声改变、对侧是否有癌、TPOAB、TGAB组间差异无统计学意义(P均>0.05)。进一步分析结节成分与病理类型的关系,结果表明,低风险肿瘤相对于良性结节实性比例更高,差异有统计学意义(χ^(2)=9.571,P=0.002);而恶性结节相对于低风险肿瘤(χ^(2)=2.143,P=0.143),恶性结节相对于良性结节(χ^(2)=2.165,P=0.141)囊实性比例差异均无统计学意义。结论虽然各种版本的甲状腺影像报告与数据系统均将TI-RADS 3级结节认定为良性可能,但恶性结节在C-TI-RADS 3类甲状腺结节中仍占一定比例,需要重视诸如囊实性结节、甲状腺滤泡性肿瘤、甲状腺髓样癌等超声征象不典型的甲状腺结节。在评估结节良恶性时,超声引导下细针穿刺细胞病理学检查是必要的,需要重视标本不满意或无法诊断的情况,提高诊断的准确性。 展开更多
关键词 中国版甲状腺影像报告及数据系统(c-TI-RADS)3类 甲状腺结节 临床特点
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Insulation characteristics of triple mixtures of c-C_4F_8/N_2/CO_2 under lightning impulse voltage
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作者 Zhouming ZHANG Zhaorui NI +1 位作者 Dengming XIAO Yizhou WU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第10期112-117,共6页
This paper has researched the insulation characteristics of 10% c-C4F8/N2/CO2 mixtures under lightning impulse voltage by experiment. It is shown that the positive and negative lightning impulse breakdown voltages of ... This paper has researched the insulation characteristics of 10% c-C4F8/N2/CO2 mixtures under lightning impulse voltage by experiment. It is shown that the positive and negative lightning impulse breakdown voltages of 10%c-C4F8/N2/CO2 gas mixtures rise linearly as the electrode gap distance and gas pressure increase and under the same conditions, the positive lightning impulse breakdown voltage of the gas mixtures is always higher than the negative lightning impulse breakdown voltage. As the gas mixtures have a little higher liquefied temperature than SF6 and the comprehensive GWP is about 5% of SF6, and the positive and negative lightning impulse breakdown voltages can both reach 60% of SF6, 10%c-C4F8/N2/CO2 gas mixtures can be applied as insulation gas in electrical equipment such as C-GIS, GIT, GIL and so on. 展开更多
关键词 SF6 alternative insulation characteristics lightning impulse voltage c-c4F8 gas mixtures
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C型外包花纹钢-混凝土界面粘结强度推出试验研究
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作者 陈丽华 周璐洁 +1 位作者 徐海波 董丽娟 《建筑结构》 北大核心 2024年第1期17-24,共8页
为探究带拉条式C型外包花纹钢-混凝土的粘结强度及粘结滑移性能,考虑钢板的花纹高度、混凝土强度、拉条间距、截面宽度和翼缘截面形式对试件粘结强度的影响,设计制作了12个带拉条的C型外包花纹钢-混凝土推出试件。分析各试件的破坏过程... 为探究带拉条式C型外包花纹钢-混凝土的粘结强度及粘结滑移性能,考虑钢板的花纹高度、混凝土强度、拉条间距、截面宽度和翼缘截面形式对试件粘结强度的影响,设计制作了12个带拉条的C型外包花纹钢-混凝土推出试件。分析各试件的破坏过程、荷载-滑移曲线、钢板应变沿纵向分布规律及特征粘结强度;综合考虑各影响因素,统计回归得出特征粘结强度的计算公式。研究结果表明:增大花纹高度是改善粘结性能最有效的途径;特征粘结强度随着混凝土强度的增大呈增大趋势,随着截面宽高比和拉条间距的增大呈减小趋势;在同等条件下,翼缘内翻试件的粘结性能优于翼缘外翻试件;特征粘结强度的回归公式能够较好地拟合试验结果。 展开更多
关键词 c型外包钢 花纹钢板 特征粘结强度 推出试验 荷载-滑移曲线
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