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Estimation of Peanut Maturity Using Color Image Analysis
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作者 Wei-Zhen Liang Kendall R. Kirk +1 位作者 James S. Thomas Andrew C. Warner 《American Journal of Plant Sciences》 CAS 2024年第8期617-635,共19页
Peanuts pods grow underground and mature unevenly, resulting that choosing the correct time to harvest is more complicated than other crops. Pod maturity can be determined by blasting with a pressure washer to remove ... Peanuts pods grow underground and mature unevenly, resulting that choosing the correct time to harvest is more complicated than other crops. Pod maturity can be determined by blasting with a pressure washer to remove outer skin of the pod (exocarp) to expose the color of the middle layer (mesocarp). The mesocarp color changes with maturity from white to yellow, orange, brown and finally black. The sum of percentage from orange, brown, and black mesocarp (OBB) color and black color (BL) represents the kernels that are mature enough to harvest. The goal of this research is to identify methodologies to estimate OBB and BL of the pods using RGB images taken in the field and validate the proposed model using other pod images. The Mahalanobis distance classification method was used to process sets of images and calculate pod area (number of pixels) corresponding to two classes (mesocarp and background) with nine different color groups. The results showed a performance of 94% effectiveness for mesocarp using Mahalanobis distance classification. Statistical regression for OBB and BL was developed based on 315 images of peanut pods taken from the field. The R2 and root mean square error of predicted and actual OBB were 0.93 and 4.1%, respectively. The R2 and root mean square error of predicted and actual BL were 0.88 and 1.8%, respectively. The validation of OBB using other images provided reasonable estimation (R2 = 0.98 and RMSE = 2.73%). This study introduces a novel, cost-effective, and non-destructive method for estimating peanut maturity using RGB imagery and Mahalanobis distance classification in the field. This innovative approach addresses the limitations of traditional methods and offers a robust alternative for real-time maturity assessment. 展开更多
关键词 Peanut maturity MESOCARP EXOCARP Mahalanobis Distance Statistical Regression
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Studies of the Variability of Primary Metabolites in the Epicarp, Mesocarp and Seed of Dacryodes edulis Fruit at Taste Maturity
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作者 Etou Ossibi Grace Jokael Mbon Nguékou Chrichina +2 位作者 Ongouya Mouekouba Dalcantara Liana Mpika Joseph Attibayeba   《Advances in Biological Chemistry》 CAS 2024年第2期64-72,共9页
The fruits of Dacryodes edulis are rich in biologically active substances, which makes them of great interest in terms of validation. In this study, we targeted the primary metabolites in the epicarp, the mesocarp and... The fruits of Dacryodes edulis are rich in biologically active substances, which makes them of great interest in terms of validation. In this study, we targeted the primary metabolites in the epicarp, the mesocarp and the seed of the fruit of Dacryodes edulis at taste maturity, which were selected for their nutritional quality and its appreciation throughout the Gulf of Guinea area, which is very popular because of its large size, texture and special taste. The evaluation of total carbohydrates, total lipids and soluble proteins in the epicarp, mesocarp and seed of the fruit at taste maturity was made from spectrophotometer measurements. The overall analysis of the results of the present study shows that total carbohydrates, total lipids and proteins accumulate more in the seed with respectively 251.33 ± 1.15 mg/g DM;9.92 ± 0.201 mg/g DM and 55.075 ± 0.024 mg/g DM. Likewise, the results indicate low concentrations of total carbohydrates and total lipids in the epicarp with respectively 245 ± 1 mg/g DM and 4.77 ± 0.047 mg/g DM, on the other hand, it is the mesocarp which presents the lowest content of soluble proteins: 28.075 ± 3.231 mg/g DM. This variation could be linked to the nature of the compartment, more particularly to the storage location. This comparative study could lead to the valorization of the seed of the fruit of Dacryodes edulis for its richness in metabolites and arouse significant interest in nutrition. 展开更多
关键词 Dacryodes edulis FRUIT Taste maturity Epicarp MESOCARP SEED
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Neurovascular unit on a chip:the relevance and maturity as an advanced in vitro model
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作者 Sujey Palma-Florez Anna Lagunas Mònica Mir 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1165-1166,共2页
The brain is a high-energy demanding organ,consuming around 20%of the metabolic energy generated.To fulfill this demand,cerebral blood flow(CBF)supplies oxygen and glucose continuously through the intricate network of... The brain is a high-energy demanding organ,consuming around 20%of the metabolic energy generated.To fulfill this demand,cerebral blood flow(CBF)supplies oxygen and glucose continuously through the intricate network of cerebral blood vessels.Although for many years brain activity and blood flow were conceived as independent processes,MRI-based functional brain imaging demonstrated that there is a coupling between them. 展开更多
关键词 CEREBRAL maturity consuming
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A Proposed Approach for Measuring Maturity Level of Software Delivery
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作者 Osama Hassan Mansour Atef Raslan Nagy Ramadan 《Journal of Software Engineering and Applications》 2024年第5期228-245,共18页
Software delivery is vital for modern organizations, driving innovation and competitiveness. Measuring an organization’s maturity in software delivery is crucial for efficiency and quality. The Capability Maturity Mo... Software delivery is vital for modern organizations, driving innovation and competitiveness. Measuring an organization’s maturity in software delivery is crucial for efficiency and quality. The Capability Maturity Model (CMM) framework provides a roadmap for improvement but assessing an organization’s CMM Level is challenging. This paper offers a quantitative approach tailored to the CMM framework, using Goal-Question-Metric (GQM) frame-works for each key process area (KPA). These frameworks include metrics and questions to compute maturity scores effectively. The study also refines practices into questions for a thorough assessment. The result is an Analysis Matrix that calculates weighted scores and an overall maturity score. This approach helps organizations assess and enhance their software delivery processes systematically, aiming for improved practices and growth. 展开更多
关键词 CMM CMMI Software Delivery maturity KPAs GQM PRACTICES
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Correlation analysis of interstitial maturity and prognosis of colorectal cancer:Meta-analysis
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作者 Zhen-Jun Liu Xu-Wen Zhang +1 位作者 Qi-Qi Liu Shao-Zhao Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2816-2825,共10页
BACKGROUND To investigate the relationship between interstitial maturity and prognosis of colorectal cancer.AIM To examine the correlation between interstitial maturity and the prognosis of colorectal cancer.METHODS T... BACKGROUND To investigate the relationship between interstitial maturity and prognosis of colorectal cancer.AIM To examine the correlation between interstitial maturity and the prognosis of colorectal cancer.METHODS The paper database PubMed,EMBASE,Cochranelibrary,Springerlink,CNKI,and Wanfang database were searched until December 2023."tumor stroma maturity""desmoplastic stroma reaction""desmoplastic reaction""stroma reaction""degree of stroma reaction""stroma classification""stroma density""colorectal cancer""colon cancer""rectal cancer""prognosis"were searched for the search terms.Two system assessors independently screened the literature quality according to the inclusion exclusion criteria,Quality evaluation and data extraction were performed for the included literatures,and meta-analysis was performed for randomized control trials included at using Review Manager 5.2 software.RESULTS Finally,data of 9849 patients with colorectal cancer from 19 cosets in 15 literatures were included,including 4339 patients with mature type(control group),3048 patients with intermediate type(intermediate group)and 2456 patients with immature type(immature group).The results of meta-analysis showed:Relapse-free survival[hazard ratio(HR)=2.66,95%confidence interval(CI):2.30-3.08;P<0.00001],disease-free survival(HR=3.68,95%CI:2.33-5.81;P<0.00001)and overall survival(HR=1.70,95%CI:1.53-1.87;P<0.00001)were significantly lower than those in mature group(control group);relapse-free survival(HR=1.36,95%CI:1.17-1.59;P<0.0001)and disease-free survival rate(HR=1.85,95%CI:1.53-2.24;P<0.0001)was significantly lower than the mature group(control group).CONCLUSION There is the correlation between tumor interstitial maturity and survival prognosis of colorectal cancer,and different degrees of tumor interstitial maturity have a certain impact on the quality of life of colorectal cancer patients. 展开更多
关键词 Colorectal tumor Survival prognosis Tumor interstitial maturity Systematic review META-ANALYSIS
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“Component flow”conditions and its effects on enhancing production of continental medium-to-high maturity shale oil
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作者 ZHAO Wenzhi BIAN Congsheng +8 位作者 LI Yongxin LIU Wei QIN Bing PU Xiugang JIANG Jianlin LIU Shiju GUAN Ming DONG Jin SHEN Yutan 《Petroleum Exploration and Development》 SCIE 2024年第4期826-838,共13页
Based on the production curves,changes in hydrocarbon composition and quantities over time,and production systems from key trial production wells in lacustrine shale oil areas in China,fine fraction cutting experiment... Based on the production curves,changes in hydrocarbon composition and quantities over time,and production systems from key trial production wells in lacustrine shale oil areas in China,fine fraction cutting experiments and molecular dynamics numerical simulations were conducted to investigate the effects of changes in shale oil composition on macroscopic fluidity.The concept of“component flow”for shale oil was proposed,and the formation mechanism and conditions of component flow were discussed.The research reveals findings in four aspects.First,a miscible state of light,medium and heavy hydrocarbons form within micropores/nanopores of underground shale according to similarity and intermiscibility principles,which make components with poor fluidity suspended as molecular aggregates in light and medium hydrocarbon solvents,such as heavy hydrocarbons,thereby decreasing shale oil viscosity and enhancing fluidity and outflows.Second,small-molecule aromatic hydrocarbons act as carriers for component flow,and the higher the content of gaseous and light hydrocarbons,the more conducive it is to inhibit the formation of larger aggregates of heavy components such as resin and asphalt,thus increasing their plastic deformation ability and bringing about better component flow efficiency.Third,higher formation temperatures reduce the viscosity of heavy hydrocarbon components,such as wax,thereby improving their fluidity.Fourth,preservation conditions,formation energy,and production system play important roles in controlling the content of light hydrocarbon components,outflow rate,and forming stable“component flow”,which are crucial factors for the optimal compatibility and maximum flow rate of multi-component hydrocarbons in shale oil.The component flow of underground shale oil is significant for improving single-well production and the cumulative ultimate recovery of shale oil. 展开更多
关键词 continental facies pure shale type shale oil medium-to-high maturity shale oil micro-nanopores multi-component hydrocarbons component flow similarity and intermiscibility molecular aggregate
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Exploration of the Maturity Evaluation of College Students’Innovation and Entrepreneurship Projects Based on Computer Database Technology
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作者 Shuai Yuan 《Journal of Electronic Research and Application》 2024年第6期89-95,共7页
The college innovation and entrepreneurship program is a powerful means to enhance students’innovation and entrepreneurship skills.Evaluating the maturity of innovation and entrepreneurship projects can stimulate stu... The college innovation and entrepreneurship program is a powerful means to enhance students’innovation and entrepreneurship skills.Evaluating the maturity of innovation and entrepreneurship projects can stimulate students’enthusiasm and initiative to participate.Utilizing computer database technology for maturity evaluation can make the process more efficient,accurate,and convenient,aligning with the needs of the information age.Exploring strategies for applying computer database technology in the maturity evaluation of innovation and entrepreneurship projects offers valuable insights and directions for developing these projects,while also providing strong support for enhancing students’innovation and entrepreneurship abilities. 展开更多
关键词 DATABASE Innovation and entrepreneurship projects maturity evaluation
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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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Evaluation of KTJT-1,an early-maturity mutant of sweet sorghum acquired by carbon ions irradiation
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作者 董喜存 李文建 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第2期47-50,共4页
Sweet sorghum has the potential of becoming a useful energy crop.An early-maturity mutant of sweet sorghum,KFJT-1,was obtained by carbon ions irradiation of KFJT-CK,a wild plant.In this paper,we evaluate the mutant fr... Sweet sorghum has the potential of becoming a useful energy crop.An early-maturity mutant of sweet sorghum,KFJT-1,was obtained by carbon ions irradiation of KFJT-CK,a wild plant.In this paper,we evaluate the mutant from the length and fresh weight of radicle and leaves after seed germination,the growth rate at the elongation stage,and the internodal parameters under field trail condition.The results showed that the seedling growth of KFJT-1 was inhibited by carbon ions irradiation,and the leaf length,the fresh weight of radicle and leaves from KFJT-1 decreased by 15.32%,76.27%,and 27.08%than those of KFJT-CK,respectively.However,the growth rate of KFJT-1 on July 12,July 27 and August 1 increased by 16.19%,59.28%and26.87%,respectively,compared with the KFJT-CK.The stalk diameter,total biomass yield and sugar content of KFJT-1 was higher than those of KFJT-CK,despite that the plant height of KFJT-1 was significantly less than KFJT-CK(P < 0.05).In addition,KFJT-1 differed from KFJT-CK in the internodal length,weight and sugar content.In conclusion,the early-maturity mutant of KFJT-1 will be a promising variety for sweet sorghum industrialization in Gansu province,China. 展开更多
关键词 早熟突变 甜高粱 碳离子 离子辐照 评价 收购 节间长度 能源作物
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E-government maturity model and its evaluation 被引量:4
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作者 黄梦醒 邢春晓 杨吉江 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期389-392,共4页
In order to ensure e-government construction healthily,rapidly and orderly develop,an e-government maturity model(EGMM)is proposed based on a software capability maturity model (CMM)and a project management maturi... In order to ensure e-government construction healthily,rapidly and orderly develop,an e-government maturity model(EGMM)is proposed based on a software capability maturity model (CMM)and a project management maturity model(PMMM). Five levels of maturity in e-government development process are constructed,which include network infrastructure,information serving,information interactive,information sharing and comprehensive integrating.An index system of e-government maturity is put forward,and then an e-government maturity levels evaluation method is presented,which can provide clear,detailed and efficient decision information and investment directions of e-government for decision-makers.The EGMM and its maturity evaluation method are helpful for improving the construction of e-government. 展开更多
关键词 E-GOVERNMENT maturity model index system EVALUATION
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Synergistic Effects of Nitric Oxide and Harvest Maturity on Quality of Honey Peach during Cold Storage
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作者 胡花丽 李鹏霞 +1 位作者 王毓宁 李志强 《Agricultural Science & Technology》 CAS 2013年第4期549-553,共5页
In this study, peaches of cv. 'Sui Yuan' with different maturities were treated with 0.05 mM sodium nitroprusside (SNP), a nitric oxide donor, for 5 min, at 28℃, and then stored at 0-1.5℃ for 30 days. Untreated ... In this study, peaches of cv. 'Sui Yuan' with different maturities were treated with 0.05 mM sodium nitroprusside (SNP), a nitric oxide donor, for 5 min, at 28℃, and then stored at 0-1.5℃ for 30 days. Untreated fruits stored under the same conditions were used as control fruits in the experiment. The browning level, activities of polyphenol oxidase (PPO), peroxydase (POD) and superoxide dismutase (SOD), and quality parameters (firmness, titratable acid, total soluble solids and total sugar) were analyzed. The results showed that the firmness of SNP-treated fruit at different stage of maturity were higher than that of the control fruit after storage for 30 days. However, no significant effect was found on total soluble solid content. The titratable acid content of low maturity fruit was higher in SNP-treated one than that of the control, but the titratable acid content of high maturity fruit treated by SNP was lower than that of the control on 10th and 30th day. In addition, the combination of SNP treatment and high maturity resulted in higher activities of SOD, lower activity of PPO and POD, lower browning level. Therefore, the combination of high maturity and SNP treatment might be a useful method to well maintain honey peach fruit quality during cold storage. 展开更多
关键词 Honey peach Harvest maturity Sodium nitroprusside treatment QUALITY
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Effects of Ploughing Astragalus sinicus at Maturity Stage on Rice Yield and Soil Properties of Paddy Field
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作者 王伯诚 赖小芳 +2 位作者 陈银龙 项玉英 陈剑 《Agricultural Science & Technology》 CAS 2013年第12期1792-1796,1803,共6页
[Objective] The effects of ploughing Astragalus sinicus at maturity stage as green manure on paddy soil properties were studied to provide references for ad- vancing the green manure production and field sustainable d... [Objective] The effects of ploughing Astragalus sinicus at maturity stage as green manure on paddy soil properties were studied to provide references for ad- vancing the green manure production and field sustainable development. [Methods] A three-year field positioning experiment was carried out. In the first year, five differ- ent levels (0, 2.81, 5.61, 8.42, 11.23 t/hm~) of Astragalus sinicus ploughed at matu- rity stage were designed. And in the next two years, the amounts of ploughed As- tragalus sinicus at maturity stage were based on the natural growth amounts of As- tragalus sinicus at maturity stage of the former year in each plot field. The yields of Astragalus sinicus at maturity stage were estimated and ploughed directly before rice transplanting. Rice yield, soil nutrients, biological properties and water-stable aggre- gates of paddy fields were measured as well. [Results] The effective panicles and rice yields increased significantly after ploughing Astragalus sinicus at maturity stage. Meanwhile, the organic acid content in paddy field increased and the activities of soil phosphatases, invertase and catalase were higher. The soil dissolved organic carbon also increased with the increasing application of green manure. However, excess amount of green manure inhibited the soil microbial biomass carbon content. The macro aggregates and micro aggregates gathered to middle aggregates. [Conclusion] As green manure, the use of Astragalus sinicus at maturity stage could improve soil physiochemical and biological properties, improve soil fertility and increase rice yield significantly. But the ploughing amount of Astragalus sinicus at maturity stage before rice transplanting should be less than 8.42 t/hm2 (dry weight. 展开更多
关键词 Astragalus sinicus at maturity stage PLOUGHING Rice yield Paddy soil nutrients Soil properties
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DEBT MATURITY STRUCTURE IN PROJECT FINANCING
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作者 黄福广 《Transactions of Tianjin University》 EI CAS 2001年第4期261-264,共4页
Based on the concept of debt duration,this paper proposes the elasticity of cash flow.Then,the debt maturity structure in project financing is discussed.The results show that in the project financing structure,the deb... Based on the concept of debt duration,this paper proposes the elasticity of cash flow.Then,the debt maturity structure in project financing is discussed.The results show that in the project financing structure,the debt maturity structure is closely related with debt capacity.Higher debt ratio requires short term debt,and vise versa. 展开更多
关键词 project financing debt maturity structure DURATION debt ratio
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Emma's Growth from Innocence to Maturity
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作者 周道凤 《海外英语》 2013年第21期245-247,共3页
Emma is one of the most successful novels by Jane Austen.This thesis analyzed the background of its heroine Emma’s growth background,her growth from conceit,snobbery,domination to maturity,and the causes of her chara... Emma is one of the most successful novels by Jane Austen.This thesis analyzed the background of its heroine Emma’s growth background,her growth from conceit,snobbery,domination to maturity,and the causes of her character transformation.Her psychological growth process from innocence to maturity demonstrates women’s growth and progress in the early 19th cen tury,and inspires modern women to gradually improve in personality and better present their charms of maturity. 展开更多
关键词 EMMA GROWTH INNOCENCE maturity
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Curing Characteristics and Suitable Harvest Maturity of Fresh Flue-cured Tobacco Leaves in Ankang Tobacco Growing Areas 被引量:2
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作者 朱峰 饶智 +3 位作者 沈始权 孙福山 任杰 肖头杰 《Agricultural Science & Technology》 CAS 2015年第4期815-819,共5页
CuItivars K326, Yunyan 87 and Guiyan 4 were used to investigate the curing characteristics and suitabIe harvest maturity of fresh fIue-cured tobacco Ieaves in Ankang tobacco growing areas. ResuIts indicated that the w... CuItivars K326, Yunyan 87 and Guiyan 4 were used to investigate the curing characteristics and suitabIe harvest maturity of fresh fIue-cured tobacco Ieaves in Ankang tobacco growing areas. ResuIts indicated that the water Ioss of K326 was sIow,and the Ieaves were resistant to curing and reIative easiIy to cure. The water Ioss of Yunyan 87 and Guiyan 4 were quick, and the Ieaves with normal resistance to curing were reIative difficuIt to cure. For Guiyan 4, the shrinkage of CM1 maturity was the Iargest. For K326 and Yunyan 87, the shrinkages of CM2 maturity were the Iargest whiIe the shrinkage of CM1 maturity was the Iowest, but the difference did not reach statistical significance. The proportion of top-middIe-grade tobacco Ieaves and average price for K326 were the highest with XM2, CM2 and BM2 maturity, and for Yunyan 87 were XM1, CM3 and BM2 maturity. For K326, Ieaves with XM2, CM2 and BM2 maturity showed the balanced chemical components and the best smoking quality. 展开更多
关键词 FIue-cured tobacco Curing characteristic maturity Ankang City of Shaanxi Province
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Microbiological parameters and maturity degree during composting of Posidonia oceanica residues mixed with vegetable wastes in semi-arid pedo-climatic condition 被引量:35
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作者 SAIDI Neyla KOUKI Soulwene +4 位作者 M'HIRI Fadhel JEDIDI Naceur MAHROUK Meriam HASSEN Abdennaceur OUZARI Hadda 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第10期1452-1458,共7页
The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues (VR) collected from markets of Tunis City with ... The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues (VR) collected from markets of Tunis City with residues of Posidonia oceanica (PoR), collected from Tunis beaches. The accumulation in beaches (as well as their removal) constitutes a serious environmental problem in all Mediterranean countries particularly in Tunisia. Aerobic-thermophilic composting is the most reasonable way to profit highly-valuable content of organic matter in these wastes for agricultural purposes. The physical, chemical, and biological parameters were monitored during composting over 150 d. The most appropriate parameters were selected to establish the maturity degree. The main result of this research was the deduction of the following maturity criterion: (a) C/N ratio 〈 15; (b) NH4^+-N 〈 400 mg/kg; (c) CO2-C 〈 2000 mg CO2-C/kg; (d) dehydrogenase activity 〈 1 mg TPF/g dry matter; (e) germination index (GI) 〉 80%. These five parameters, considered jointly are indicative of a high maturity degree and thus of a high-quality organic amendment which employed in a rational way, may improve soil fertility and soil quality. The mature compost was relatively rich in N (13.0 g/kg), P (4.74 g/kg) and MgO (15.80 g/kg). Thus composting definitively constitutes the most optimal option to exploit these wastes. 展开更多
关键词 soil degradation RECYCLING COMPOSTING organic amendment maturity degree
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Oil maturity assessment using maturity indicators based on methylated dibenzothiophenes 被引量:15
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作者 Li Meijun Wang T.-G +2 位作者 Shi Shengbao Zhu Lei Fang Ronghui 《Petroleum Science》 SCIE CAS CSCD 2014年第2期234-246,共13页
Aromatic fractions of 140 oils and condensates that originated from different types of source rocks (marine shale,terrestrial shale and marine carbonate) were analyzed using gas chromatographymass spectrometry (GC... Aromatic fractions of 140 oils and condensates that originated from different types of source rocks (marine shale,terrestrial shale and marine carbonate) were analyzed using gas chromatographymass spectrometry (GC-MS) to investigate the relative distributions of methylated dibenzothiophenes with respect to thermal maturity.The positions of methyl groups of trimethyldibenzothiophene isomers (TMDBTs) including those used in the definition of maturity indicator TMDBT index in previous studies were firmly identified by co-elution of internal standards in GC-MS analysis and by comparing with reported retention indices.A new maturity ratio related to dimethyldibenzothiophenes (DMDBTs) is proposed on the basis of the differences in thermodynamic stability among different DMDBT isomers.Another maturity index (TMDBT-I2) based on TMDBTs is also suggested on the basis of our empirical observations and presumed thermodynamic stability of TMDBT isomers.These two newly proposed (2,6 + 3,6)-/1,4-DMDBT ratio and TMDBT-I2 correlate well with MDR (4-/1-methyldibenzothiophene)and 2,4-/1,4-DMDBT ratios,suggesting their common chemical reaction mechanisms and similar behavior with increasing maturity.Therefore,they can be effectively applied for maturity assessments.Furthermore,the TMDBTs related maturity parameters are more reliable for over-mature oils and condensates due to the relatively higher concentrations of thermodynamically unstable TMDBT isomers,i.e.1,4,6-,1,4,8-and 3,4,6-TMDBT in this study than those of 1-methyldibenzothiophene (1-MDBT) or 1,4-DMDBT.In contrast with 4,6-/1,4-DMDBT,the newly proposed (2,6 + 3,6)-/1,4-DMDBT ratios for oils that originated from different types of source rocks have approximately same relationship with the oil maturity (Rc %).This suggests that the lithology and organic facies may have relatively less influence on (2,6 + 3,6)-/1,4-DMDBT ratio compared to 4,6-/1,4-DMDBT.The maturity parameters based on methylated dibenzothiophenes are particularly useful in the maturity assessments of post-and over-mature oils and condensates and can complement maturity indicators based on steranes and terpanes. 展开更多
关键词 DIBENZOTHIOPHENE maturity indicator molecular thermodynamic stability sedimentaryorganic matter
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The Occurrence of Oleananes in the Beibuwan Basin and Its Application to the Study of Maturity and Oil-Source Rock Correlation 被引量:9
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作者 LI Meijun WANG Tieguan +4 位作者 LIU Ju ZHANG Meizhu LU Hong MA Qinglin GAO Lihui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期585-595,共11页
The oleanane parameter, i.e., OP (oleananes/(oleananes+C30hopanes)) in the two sedimentary columns of the Beibuwan Basin, South China Sea, can be used to delimit the top of oil generation window, with Ro (/%) o... The oleanane parameter, i.e., OP (oleananes/(oleananes+C30hopanes)) in the two sedimentary columns of the Beibuwan Basin, South China Sea, can be used to delimit the top of oil generation window, with Ro (/%) of 0.53 in Well M1 and 0.55 in Wells H1/Hd1/Hd2, respectively. Comparing with vitrinite reflectance (Ro/%), the OP features a dynamic range and can indicate the oil generation window more precisely. By using OP and other geochemical indices, the oil-source correlation is also conducted. It suggests that the oils in wells M1 and M2 are derived from the source rocks in situ. The mudstone in Huachang uplift is not the main source rocks for oils in this area, The OP is also a useful oil-source correlation parameter in some Tertiary lacustrine basins. 展开更多
关键词 oleanane parameter (OP) BIOMARKER maturity oil-source correlation Fushan Depression
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Origin and accumulation of high-maturity oil and gas in deep parts of the Baxian Depression, Bohai Bay Basin, China 被引量:11
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作者 Zhao Xianzheng Jin Qiang +5 位作者 Jin Fengming Ma Peng Wang Quan Wang Jing Ren Chunling Xi Qiuling 《Petroleum Science》 SCIE CAS CSCD 2013年第3期303-313,共11页
Great quantities of light oil and gas are produced from deep buried hill reservoirs at depths of 5,641 m to 6,027 m and 190 ℃ to 201 ℃ in the Niudong-1 Well, representing the deepest and hottest commercial hydrocarb... Great quantities of light oil and gas are produced from deep buried hill reservoirs at depths of 5,641 m to 6,027 m and 190 ℃ to 201 ℃ in the Niudong-1 Well, representing the deepest and hottest commercial hydrocarbons discovered in the Bohai Bay Basin in eastern China. This discovery suggests favorable exploration prospects for the deep parts of the basin. However, the discovery raises questions regarding the genesis and accumulation of hydrocarbons in deep reservoirs. Based on the geochemical features of the hydrocarbons and characteristics of the source rocks as well as thermal simulation experiments of hydrocarbon generation, we conclude that the oil and gas were generated from the highly mature Sha-4 Member (Es4) source rocks instead of thermal cracking of crude oils in earlier accumulations. The source kitchen with abnormal pressures and karsted carbonate reservoirs control the formation of high-maturity hydrocarbon accumulations in the buried hills (i.e., Niudong-1) in conjunction with several structural-lithologic traps in the ES4 reservoirs since the deposition of the upper Minghuazhen Formation. This means the oil and gas exploration potential in the deep parts of the Baxian Depression is probably high. 展开更多
关键词 High mature oil and gas ORIGIN ACCUMULATION deep part of Baxian Depression
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Mapping QTL underlying tuber starch content and plant maturity in tetraploid potato 被引量:4
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作者 Jianwu Li Yihang Wang +6 位作者 Guohong Wen Gaofeng Li Zhang Li Rong Zhang Sheng Ma Jun Zhou Conghua Xie 《The Crop Journal》 SCIE CAS CSCD 2019年第2期261-272,共12页
Tuber starch content and plant maturity are two important agronomic traits of potato. To investigate the complex genetic basis of these traits in the cultivated potato, as well as the relationship between them, we dev... Tuber starch content and plant maturity are two important agronomic traits of potato. To investigate the complex genetic basis of these traits in the cultivated potato, as well as the relationship between them, we developed a linkage map in a tetraploid population of 192 clones derived from the cross Longshu 8 × Zaodabai and mapped quantitative trait loci(QTL) for tuber starch content and plant maturity using data collected in three diverse environments over two years. We detected eleven QTL for tuber starch content distributed on seven chromosomes, of which four, on chromosomes I, II, and VIII, were expressed in at least three environments. For plant maturity, we identified six QTL on chromosomes II, IV,V, VII, and XI, one of which, on chromosome V, showed LOD peaks ranging from 45.2 to 62.5 cM and explained 21.6%–26.6% of phenotypic variation was expressed in five of the six environments. Because the reproducible QTL for plant maturity and tuber starch content mapped to different chromosomes and neither overlapping QTL, nor any genetic interaction between QTL were detected, we infer that tuber starch content and plant maturity are controlled by independent genetic loci. This inference supports the prospect of breeding potato for both early maturity and high starch content. 展开更多
关键词 POTATO QTL TETRAPLOID TUBER starch content PLANT maturity
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