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Assessment of spermatogenesis in camels via seminiferous tubule staging and testosterone profiling
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作者 Saif Ullah Abdul Quddus +7 位作者 Quanwei Wei Wael Ennab Sheeraz Mustafa Jiahao Sun Rahmani Mohammad Malyar Abdul Baseer Dagan Mao Fangxiong Shi 《Asian pacific Journal of Reproduction》 CAS 2024年第3期133-142,共10页
Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 drom... Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 dromedary bull camels aged 7 to 8 at a local abattoir.The histological assessment involved tissue processing,hematoxylin and eosin(H&E)staining,and examination under a microscope.Stereological analysis,germ cell identification,and assessment of seminiferous tubules and maturation were conducted.Testosterone assay was performed by radioimmunoassay using blood samples collected at regular intervals.Results:The study revealed 12 phases of the dromedary camel's seminiferous epithelium cycle,highlighting distinct morphological characteristics and cellular processes.Acrosomal migration,maturation,cap formation,and the Golgi-mediated synthesis of proacrosomal vesicles were also explained in dimension,as were the steps of acrosome biogenesis.Spermatids and mature sperm cells were present when spermatogenesis phases were examined.An analysis of the dimensions of seminiferous tubules revealed specific measures for diameter,area,and epithelial height about luminal characteristics.Moreover,there were noticeable variations in the serum testosterone concentrations during the study period,indicating temporal dynamics.Conclusions:This study outlines the spermatogenesis process in dromedary camels across 12 stages,emphasizing cellular dynamics and acrosomal biogenesis.It also provides seminiferous tubule measurements and observes seasonal testosterone fluctuations,offering insights into reproductive regulation and potential strategies for camel breeding conservation. 展开更多
关键词 SPERMATOGENESIS CAMEL Testosterone profile Morphological staging
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Predicting Age and Gender in Author Profiling: A Multi-Feature Exploration
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作者 Aiman Muhammad Arshad +2 位作者 Bilal Khan Sadique Ahmad Muhammad Asim 《Computers, Materials & Continua》 SCIE EI 2024年第5期3333-3353,共21页
Author Profiling (AP) is a subsection of digital forensics that focuses on the detection of the author’s personalinformation, such as age, gender, occupation, and education, based on various linguistic features, e.g.... Author Profiling (AP) is a subsection of digital forensics that focuses on the detection of the author’s personalinformation, such as age, gender, occupation, and education, based on various linguistic features, e.g., stylistic,semantic, and syntactic. The importance of AP lies in various fields, including forensics, security, medicine, andmarketing. In previous studies, many works have been done using different languages, e.g., English, Arabic, French,etc.However, the research on RomanUrdu is not up to the mark.Hence, this study focuses on detecting the author’sage and gender based on Roman Urdu text messages. The dataset used in this study is Fire’18-MaponSMS. Thisstudy proposed an ensemble model based on AdaBoostM1 and Random Forest (AMBRF) for AP using multiplelinguistic features that are stylistic, character-based, word-based, and sentence-based. The proposed model iscontrasted with several of the well-known models fromthe literature, including J48-Decision Tree (J48),Na飗e Bays(NB), K Nearest Neighbor (KNN), and Composite Hypercube on Random Projection (CHIRP), NB-Updatable,RF, and AdaboostM1. The overall outcome shows the better performance of the proposed AdaboostM1 withRandom Forest (ABMRF) with an accuracy of 54.2857% for age prediction and 71.1429% for gender predictioncalculated on stylistic features. Regarding word-based features, age and gender were considered in 50.5714% and60%, respectively. On the other hand, KNN and CHIRP show the weakest performance using all the linguisticfeatures for age and gender prediction. 展开更多
关键词 Digital forensics author profiling for security AdaBoostM1 random forest ensemble learning
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AMachine Learning Approach to User Profiling for Data Annotation of Online Behavior
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作者 Moona Kanwal Najeed AKhan Aftab A.Khan 《Computers, Materials & Continua》 SCIE EI 2024年第2期2419-2440,共22页
The user’s intent to seek online information has been an active area of research in user profiling.User profiling considers user characteristics,behaviors,activities,and preferences to sketch user intentions,interest... The user’s intent to seek online information has been an active area of research in user profiling.User profiling considers user characteristics,behaviors,activities,and preferences to sketch user intentions,interests,and motivations.Determining user characteristics can help capture implicit and explicit preferences and intentions for effective user-centric and customized content presentation.The user’s complete online experience in seeking information is a blend of activities such as searching,verifying,and sharing it on social platforms.However,a combination of multiple behaviors in profiling users has yet to be considered.This research takes a novel approach and explores user intent types based on multidimensional online behavior in information acquisition.This research explores information search,verification,and dissemination behavior and identifies diverse types of users based on their online engagement using machine learning.The research proposes a generic user profile template that explains the user characteristics based on the internet experience and uses it as ground truth for data annotation.User feedback is based on online behavior and practices collected by using a survey method.The participants include both males and females from different occupation sectors and different ages.The data collected is subject to feature engineering,and the significant features are presented to unsupervised machine learning methods to identify user intent classes or profiles and their characteristics.Different techniques are evaluated,and the K-Mean clustering method successfully generates five user groups observing different user characteristics with an average silhouette of 0.36 and a distortion score of 1136.Feature average is computed to identify user intent type characteristics.The user intent classes are then further generalized to create a user intent template with an Inter-Rater Reliability of 75%.This research successfully extracts different user types based on their preferences in online content,platforms,criteria,and frequency.The study also validates the proposed template on user feedback data through Inter-Rater Agreement process using an external human rater. 展开更多
关键词 User intent CLUSTER user profile online search information sharing user behavior search reasons
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ABMRF:An Ensemble Model for Author Profiling Based on Stylistic Features Using Roman Urdu
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作者 Aiman Muhammad Arshad +3 位作者 Bilal Khan Khalil Khan Ali Mustafa Qamar Rehan Ullah Khan 《Intelligent Automation & Soft Computing》 2024年第2期301-317,共17页
This study explores the area of Author Profiling(AP)and its importance in several industries,including forensics,security,marketing,and education.A key component of AP is the extraction of useful information from text... This study explores the area of Author Profiling(AP)and its importance in several industries,including forensics,security,marketing,and education.A key component of AP is the extraction of useful information from text,with an emphasis on the writers’ages and genders.To improve the accuracy of AP tasks,the study develops an ensemble model dubbed ABMRF that combines AdaBoostM1(ABM1)and Random Forest(RF).The work uses an extensive technique that involves textmessage dataset pretreatment,model training,and assessment.To evaluate the effectiveness of several machine learning(ML)algorithms in classifying age and gender,including Composite Hypercube on Random Projection(CHIRP),Decision Trees(J48),Na飗e Bayes(NB),K Nearest Neighbor,AdaboostM1,NB-Updatable,RF,andABMRF,they are compared.The findings demonstrate thatABMRFregularly beats the competition,with a gender classification accuracy of 71.14%and an age classification accuracy of 54.29%,respectively.Additional metrics like precision,recall,F-measure,Matthews Correlation Coefficient(MCC),and accuracy support ABMRF’s outstanding performance in age and gender profiling tasks.This study demonstrates the usefulness of ABMRF as an ensemble model for author profiling and highlights its possible uses in marketing,law enforcement,and education.The results emphasize the effectiveness of ensemble approaches in enhancing author profiling task accuracy,particularly when it comes to age and gender identification. 展开更多
关键词 Machine learning author profiling AdaBoostM1 random forest ensemble learning text classification
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全二维气相色谱飞行时间质谱结合Napping^(■)-UFP解析清雅型和米香型白酒的香气差异 被引量:1
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作者 吴凡 范绍辉 +3 位作者 何国良 梁思宇 徐岩 唐柯 《食品与发酵工业》 CAS CSCD 北大核心 2023年第23期293-298,I0004-I0009,共12页
该研究采用全二维气相色谱飞行时间质谱(two-dimensional gas chromatography-time-of-flight mass spectrometry,GC×GC-TOFMS)结合感官分析,探究了清雅型石湾玉冰烧白酒和传统米香型白酒香气的物质和感官差异。GC×GC-TOFMS... 该研究采用全二维气相色谱飞行时间质谱(two-dimensional gas chromatography-time-of-flight mass spectrometry,GC×GC-TOFMS)结合感官分析,探究了清雅型石湾玉冰烧白酒和传统米香型白酒香气的物质和感官差异。GC×GC-TOFMS共定性出挥发性化合物400种,进一步通过香气数据库(Flavornet和Flavor DB)筛选出具有香气特征的292种香气化合物,其中酯类物质种类最多,醇类、醛酮类、萜类化合物次之。采用单因素方差分析结合主成分分析(principal component analysis,PCA)、聚类热图分析对香气化合物的半定量浓度进行分析,发现清雅型白酒在香气挥发物的种类和含量上明显区别于米香型白酒。使用Napping^(■)结合ultra flash profiling(UFP)的感官方法,明确了植物、油脂香、中药、甘草、薄荷、雪碧是清雅型白酒区别于米香型白酒的主要香气属性。该研究丰富了以大米为主要原料白酒风味化学的理论体系,也为其风味的进一步调控提供基础数据和理论依据。 展开更多
关键词 清雅型石湾玉冰烧 米香型白酒 全二维气相色谱飞行时间质谱 Napping^(■)-Ultra Flash profiling 香气
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基于不同类型快速描述分析方法的豆豉感官评价--以Napping-UFP法、FCP法和PSP法为例
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作者 谭仟 陈雪 +2 位作者 刘钰颖 王洪伟 索化夷 《食品与发酵工业》 CAS CSCD 北大核心 2023年第21期250-255,共6页
为了比较不同类型快速描述分析方法的感官评价效果,该研究分别采用Napping法结合超自选特性排序剖面(Napping-ultra-flash profiling,Napping-UFP)法、自由选择剖面(free choice profiling,FCP)法以及极化感官定位(polarized sensory po... 为了比较不同类型快速描述分析方法的感官评价效果,该研究分别采用Napping法结合超自选特性排序剖面(Napping-ultra-flash profiling,Napping-UFP)法、自由选择剖面(free choice profiling,FCP)法以及极化感官定位(polarized sensory positioning,PSP)法对不同产地的豆豉样品进行快速描述分析。结果表明,相同样品在载荷图上的位置均接近,方法准确性较高。3种方法的样品载荷图分布均相似,对不同产地的豆豉具有良好的区分度。同时,调整后的RV系数(adjusted RV coefficient,ARV)均高于0.750,进一步说明3种方法间的相关性较高;PSP法与FCP法的相关性最高,但PSP法缺少感官描述词。Napping-UFP和FCP法均可以提供产品的感官特征。综上可见,以Napping-UFP法、FCP法和PSP法为代表的快速描述分析方法均可快速实现样品区分,能有效、较准确获得各产品间感官特征差异,在食品感官评价领域具有广泛的应用前景。 展开更多
关键词 豆豉 感官特征 Napping-ufp 自由选择剖面法 极化感官定位法
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排序检验法和Napping-UFP法在皖西黄茶实物标准样研制中的应用
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作者 张莹 邱桐 +7 位作者 韩梓怡 安琪 赵潇奕 姜青 李露青 宁井铭 宛晓春 戴前颖 《茶叶科学》 CAS CSCD 北大核心 2023年第2期275-286,共12页
制定具有标准级差代表性的实物标准样对黄茶的生产流通具有重要意义。分别招募80名普通消费者和22名初级评价员,对皖西黄茶的3大类(黄芽茶、黄小茶、黄大茶)9个等级实物标准样进行排序检验及Napping-UFP法分析。结果表明,在排序检验法... 制定具有标准级差代表性的实物标准样对黄茶的生产流通具有重要意义。分别招募80名普通消费者和22名初级评价员,对皖西黄茶的3大类(黄芽茶、黄小茶、黄大茶)9个等级实物标准样进行排序检验及Napping-UFP法分析。结果表明,在排序检验法中仅依据外形可基本实现对8个标准样的判定(其中黄芽特级与一级不能判别);在Napping-UFP法中,22名初级评价员仅根据外形也能较好地区分不同等级的黄茶样品,根据香气或滋味可以准确区分黄芽茶、黄小茶和黄大茶,并能准确区分黄大茶的轻火样和足火样;同时初级评价员给出了较为丰富的描述词(外形33个,香气21个,滋味24个),外形描述词中的“绿”“黄”“多梗”,香气描述词中的“嫩香”“甜香”“烟丝”,滋味描述词中的“鲜”词频较高,可以用于皖西黄茶实物标准样的级差判别,有利于消费者的理解与接受,以及皖西黄茶的市场推广。 展开更多
关键词 皖西黄茶 黄茶标准样 排序检验法 Napping-ufp
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Molecular Profiling of Sugarcane Wine, a Traditional Fermented Beverage (Loungouila) from Madingou
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作者 Yannick Frédéric Okouakoua Nicaise Saturnin Mokémiabeka +4 位作者 Christian Aimé Kayath Moïse Doria Kaya-Ongoto Stech Anomène Eckzechel Nzaou Nkalla Lambi Ndelani Etienne Nguimbi 《American Journal of Molecular Biology》 2023年第4期197-212,共16页
A number of studies reported that traditional fermented beverages possessed pharmaceutical biomolecules involved in biocatalysis for good therapeutic effects on various pathology including tumor, diabetes, inflammatio... A number of studies reported that traditional fermented beverages possessed pharmaceutical biomolecules involved in biocatalysis for good therapeutic effects on various pathology including tumor, diabetes, inflammation, and obesity. This dimension of understanding is the prerogative of the biomolecular profile found in these fermented foods and beverages. The current work aimed to study the postfermentation molecular profile of the Congolese fermented beverage (Lougwila). The determination of pH, the acidity titratable, the distillation of sugar cane, the determination of total polyphenols and flavonoids and the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) have been used. As results, the fermenting sugar cane juice at room temperature for a period of seven days, leading to a decrease of the pH value to 4.25 ± 0.10 and increase in titratable acidity and alcohol content of at least 6.421 g/L (w/v) and 7% respectively. The polyphenol concentration of Loungouila increase from 14.9 to 20.5 mg Eq AG/g Ms after 10 days of fermentation. The flavonoid concentration varies from 1.70 to 5.22 mg Eq Cat/g Ms. among 46 isolates of Bacillus species, 55% (25/45) were able to show a very interesting clear zones in terms of cellulolytic activity with the percentage ranging from 37.3% to 83.9%, and 41.3% of amylolytic activity for the percentage ranging from 52.02% to 75%. 65.21% (30/46) of the isolates tested were found to be positive by the caseinolytic test with zones of inhibition ranging in diameter from 1.10 ± 0.09 to 3.25 ± 0.07 cm. In addition to the determination of biomolecule profile, 34.78% (16/46) of Bacillus isolates were able to produce biosurfactants with percentages ranging from 14% to 100%. Proteomic profiling of Loungouila has been investigated by using MALDI-TOF Technique. Short sequences showed 100% identity and were associated with AprE, SubC, amyE, NprE, CelA, lytF, Mut, and ykfC proteins. The National Center for Biotechnology Information (NCBI) allowed to associate short sequences to Bacillus species. 展开更多
关键词 Loungouila Molecular profiling BACILLUS POLYPHENOL Flovanoids BIOSURFACTANT
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Depth profiling of arsenian pyrite in Carlin-type ores through wet chemistry
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作者 Meizhi Yang Quan Wan +4 位作者 Xin Nie Suxing Luo Yuhong Fu Ping Zeng Wenqi Luo 《Acta Geochimica》 EI CAS CSCD 2023年第2期256-265,共10页
Enrichment of As and Au at the overgrowth rims of arsenian pyrite is a distinctive feature of Carlin-type gold ores.Revealing distribution of such key elements in high resolution is of fundamental importance yet often... Enrichment of As and Au at the overgrowth rims of arsenian pyrite is a distinctive feature of Carlin-type gold ores.Revealing distribution of such key elements in high resolution is of fundamental importance yet often proves challenging.In this study,repeated non-oxidative acid etching of ore samples from Shuiyindong gold deposit was applied to enable elemental depth profiling of goldbearing arsenian pyrite grains.ICP-OES and AAS were used to determine the dissolved Fe,As,and Au concentrations in each of the etching solutions,and XPS was carried out to exam the etched mineral surfaces.In contrast to conventional ion beam etching that may cause substantial sample damage,our acid etching method does not seem to significantly alter the composition and chemical state of the samples.The etched depths directly converted from the measured elemental concentrations can reproducibly reach a very high resolution of~1 nm,and can be conveniently controlled through varying the etching time.While the Fe and As depth profiles consistently reflect the surface oxidation property of arsenian pyrite,the Au profile displaying an obvious upward trend reveals the ore fluid evolution at the late stage of mineralization.Based on our experimental results,we demonstrate that our wet chemistry method is capable of effective depth profiling of gold ore and perhaps other geological samples,with advantages surpassing many instrumental techniques including negligible sample damage,nanoscale resolution as well as isotropic etching. 展开更多
关键词 Wet chemistry Acid etching Depth profiling Carlin-type gold deposits Arsenian pyrite
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DMMIC derivatization-assisted liquid chromatography-mass spectrometry method for metabolite profiling of the glutathione anabolic pathway in esophageal cancer tissues and cells
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作者 Li Liu Yu-Han Lu +5 位作者 Min-Dan Wang Qun-Fei Zhao Xiu-Ping Chen Hang Yin Chen-Guo Feng Fang Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第11期1365-1373,共9页
In this work,a new pyrylium derivatization-assisted liquid chromatography-mass spectrometry(LC-MS)method was developed for metabolite profiling of the glutathione anabolic pathway(GAP)in cancer tissues and cells.The p... In this work,a new pyrylium derivatization-assisted liquid chromatography-mass spectrometry(LC-MS)method was developed for metabolite profiling of the glutathione anabolic pathway(GAP)in cancer tissues and cells.The pyrylium salt of 6,7-dimethoxy-3-methyl isochromenylium tetrafluoroborate(DMMIC)was used to label the amino group of metabolites,and a reductant of dithiothreitol(DTT)was employed to stabilize the thiol group.By combining DMMIC derivatization with LC-MS,it was feasible to quantify the 13 main metabolites on the GAP in complex biological samples,which had good linearity(R^(2)=0.99810.9999),precision(interday precision of 1.6%e19.0%and intraday precision of 1.4%e19.8%)and accuracy(83.4%-115.7%).Moreover,the recovery assessments in tissues(82.5%e107.3%)and in cells(98.1%e118.9%)with GSH-^(13)C2,^(15)N,and Cys-^(15)N demonstrated the reliability of the method in detecting tissues and cells.Following a methodological evaluation,the method was applied successfully to investigate difference in the GAP between the carcinoma and para-carcinoma tissues of esophageal squamous cell carcinoma(ESCC)and the effect of p-hydroxycinnamaldehyde(CMSP)on the GAP in KYSE150 esophageal cancer cells.The results demonstrate that the developed method provides a promising new tool to elucidate the roles of GAP in physiological and pathological processes,which can contribute to research on drugs and diseases. 展开更多
关键词 Glutathione anabolic pathway Metabolite profiling DMMIC derivatization LC-MS Esophageal squamous cell carcinoma p-Hydroxycinnamaldehyde KYSE-150cell
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Thermal integrity profiling of cast-in-situ piles in sand using fiber-optic distributed temperature sensing
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作者 Jing Wang Honghu Zhu +4 位作者 Daoyuan Tan Zili Li Jie Li Chao Wei Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3244-3255,共12页
Defects in cast-in-situ piles have an adverse impact on load transfer at the pile‒soil interface and pile bearing capacity. In recent years, thermal integrity profiling (TIP) has been developed to measure temperature ... Defects in cast-in-situ piles have an adverse impact on load transfer at the pile‒soil interface and pile bearing capacity. In recent years, thermal integrity profiling (TIP) has been developed to measure temperature profiles of cast-in-situ piles, enabling the detection of structural defects or anomalies at the early stage of construction. However, using this integrity testing method to evaluate potential defects in cast-in-situ piles requires a comprehensive understanding of the mechanism of hydration heat transfer from piles to surrounding soils. In this study, small-scale model tests were conducted in laboratory to investigate the performance of TIP in detecting pile integrity. Fiber-optic distributed temperature sensing (DTS) technology was used to monitor detailed temperature variations along model piles in sand. Additionally, sensors were installed in sand to measure water content and matric suction. An interpretation method against available DTS-based thermal profiles was proposed to reveal the potential defective regions. It shows that the temperature difference between normal and defective piles is more obvious in wet sand. In addition, there is a critical zone of water migration in sand due to the water absorption behavior of cement and temperature transfer-induced water migration in the early-age concrete setting. These findings could provide important insight into the improvement of the TIP testing method for field applications. 展开更多
关键词 Geotechnical monitoring Distributed temperature sensing(DTS) Pile defect Fiber-optic thermal integrity profiling(FO-TIP) Heat transfer Pile‒soil interface
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点阵激光联合重组牛碱性细胞生长因子治疗皮脂腺增生62例疗效观察
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作者 陈丽华 彭琳琳 刘之力 《中国医疗美容》 2024年第4期64-66,共3页
目的观察Profile铒激光治疗皮脂腺增生的效果。方法对62例皮脂腺增生患者采用Profile超级平台铒激光模式进行治疗,并对资料进行回顾性分析。结果62例患者痊愈49例,显效11例,无效2例,总有效率为96.77%。术后瘢痕发生率为6.45%,3~6个月渐... 目的观察Profile铒激光治疗皮脂腺增生的效果。方法对62例皮脂腺增生患者采用Profile超级平台铒激光模式进行治疗,并对资料进行回顾性分析。结果62例患者痊愈49例,显效11例,无效2例,总有效率为96.77%。术后瘢痕发生率为6.45%,3~6个月渐平复。暂时性色素改变1~3个月后均自行消退.随访6个月后治疗区未见复发。结论Profile铒激光治疗皮脂腺增生总体疗效较好,安全有效,不良反应小,值得临床推广应用。 展开更多
关键词 皮脂腺增生 Profile铒激光
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空空导弹海洋大气自然环境试验研究 被引量:1
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作者 张艳辉 史明丽 黄帅军 《装备环境工程》 CAS 2024年第3期11-15,共5页
针对空空导弹随航母服役需求和海洋大气自然环境适应性风险,结合相关标准和研制经验,对空空导弹海洋大气自然环境试验方案设计流程、方法及要点进行了研究。提出了一套空空导弹海洋大气自然环境试验方案,可用于指导新研型号科学有效地... 针对空空导弹随航母服役需求和海洋大气自然环境适应性风险,结合相关标准和研制经验,对空空导弹海洋大气自然环境试验方案设计流程、方法及要点进行了研究。提出了一套空空导弹海洋大气自然环境试验方案,可用于指导新研型号科学有效地开展自然环境试验,为回答空空导弹海洋大气自然环境适应性指标提供了支撑。空空导弹应系统策划海洋大气自然环境试验,以尽早暴露问题,实现产品设计改进,为上舰环境适应性的提高奠定基础。同时,还应大力开展自然加速环境试验技术和动态自然环境试验技术研究工作。 展开更多
关键词 空空导弹 海洋大气 自然环境试验 试验剖面
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胜利油田GF84区块CCUS气窜封堵技术及其应用 被引量:1
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作者 王涛 张星 +3 位作者 马坤玉 韦雪 唐培忠 张代森 《大庆石油地质与开发》 CAS 北大核心 2024年第1期128-134,共7页
胜利油田GF84区块为低渗透油藏,采出程度较低,CO_(2)驱是提高该区块采收率的有效措施之一。在前期开发中注采井之间已形成明显的气窜通道,现阶段亟需进行气窜封堵,提高CO_(2)驱波及系数,实现均衡驱替。通过分析GF84区块气窜特征与开发矛... 胜利油田GF84区块为低渗透油藏,采出程度较低,CO_(2)驱是提高该区块采收率的有效措施之一。在前期开发中注采井之间已形成明显的气窜通道,现阶段亟需进行气窜封堵,提高CO_(2)驱波及系数,实现均衡驱替。通过分析GF84区块气窜特征与开发矛盾,将气窜类型划分为“裂缝型气窜”和“基质型气窜”,并制定了“裂缝封堵”和“基质调剖”的治理策略。在明确气窜特征的基础上,通过室内实验研发了硅盐树脂堵剂、CO_(2)气溶性发泡剂和高温冻胶堵剂,并形成了“硅盐树脂裂缝封堵+CO_(2)气溶性发泡剂、高温冻胶基质调剖”化学封堵分级调控技术。结果表明,该技术在GF84区块成功应用4口井,其中硅盐树脂裂缝封堵2口井,CO_(2)气溶性发泡剂基质调剖2口井,措施有效率100%,有效期在0.5 a以上。研究成果可为低渗透油田CO_(2)驱开发提供技术支撑。 展开更多
关键词 低渗透油藏 CO_(2)驱 气窜 裂缝封堵 基质调剖 胜利油田
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电子舌和气相色谱-离子迁移谱技术分析炖煮时间对松茸鸡汤风味的影响 被引量:1
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作者 李想 邓静 +4 位作者 易宇文 关雎 唐英明 张振宇 张浩 《中国食品学报》 EI CAS CSCD 北大核心 2024年第1期336-348,共13页
以雅江鲜松茸为试验材料,采用电子舌和气相色谱-离子迁移谱技术,使用主成分、正交偏最小二乘法判别分析,结合相对气味活度值分析炖煮时间对松茸鸡汤风味的影响。结果表明:鲜松茸对鸡汤滋味贡献很大,电子舌鲜味强度值从2.1提高到8.0。采... 以雅江鲜松茸为试验材料,采用电子舌和气相色谱-离子迁移谱技术,使用主成分、正交偏最小二乘法判别分析,结合相对气味活度值分析炖煮时间对松茸鸡汤风味的影响。结果表明:鲜松茸对鸡汤滋味贡献很大,电子舌鲜味强度值从2.1提高到8.0。采用GC-IMS方法共检出45种化合物,加入松茸后醛类含量从47.88%下降到21.13%,由ROAV值(128.08)确认3-甲基-1-丁醇是松茸鸡汤的关键化合物。其中,伞花烃、3-辛醇、正辛醇是松茸鸡汤的特征化合物,使松茸鸡汤呈现独特的汽油味、苔藓清香、坚果香味、蘑菇气味和金属气味。炖煮5 min后,鸡汤中松茸特征风味最明显,达到最佳食用效果。研究结果为雅江松茸鸡汤风味特征研究提供参考。 展开更多
关键词 雅江松茸 炖煮时间 电子舌 气相色谱-离子迁移谱 风味特征 滋味特征
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平面端射圆极化天线进展综述 被引量:1
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作者 吕文俊 顾珊珊 +1 位作者 殷弋帆 张文海 《南京邮电大学学报(自然科学版)》 北大核心 2024年第1期1-12,共12页
全面总结了平面端射圆极化天线的发展历程和重要突破。以正交磁偶极子和平面互补振子两大核心工作原理为主线,深入剖析平面端射圆极化天线的一般性设计方法,阐明其形态演变规律,详细介绍了平面端射圆极化天线的宽带设计技术、波束调控... 全面总结了平面端射圆极化天线的发展历程和重要突破。以正交磁偶极子和平面互补振子两大核心工作原理为主线,深入剖析平面端射圆极化天线的一般性设计方法,阐明其形态演变规律,详细介绍了平面端射圆极化天线的宽带设计技术、波束调控技术以及高增益设计技术等研究现状,最后探讨平面端射圆极化天线的可能发展方向,用于指导该领域的科学研究和工程设计。 展开更多
关键词 平面端射圆极化天线 圆极化天线 端射天线 低剖面天线
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高原肺水肿大鼠肺组织基因表达谱分析
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作者 徐刚 吴刚 +6 位作者 孙滨达 刘宝 高志奇 陈建 高钰琪 高文祥 陈德伟 《陆军军医大学学报》 CAS CSCD 北大核心 2024年第11期1235-1243,共9页
目的利用基因芯片技术分析高原肺水肿(high altitude pulmonary edema,HAPE)大鼠模型肺组织差异表达基因,为深入探讨HAPE发生的分子机制提供新线索。方法将8周龄健康雄性SD大鼠[体质量(200±20)g]按随机数字表法分为常氧对照(NC)组... 目的利用基因芯片技术分析高原肺水肿(high altitude pulmonary edema,HAPE)大鼠模型肺组织差异表达基因,为深入探讨HAPE发生的分子机制提供新线索。方法将8周龄健康雄性SD大鼠[体质量(200±20)g]按随机数字表法分为常氧对照(NC)组、脂多糖(Lipopolysaccharide,LPS)组、低压低氧(Hypoxia)组和低压低氧复合低剂量LPS(HL)组。LPS组和HL组按照每100 g体质量尾静脉注射0.1 mL浓度为0.05%的LPS溶液,NC组和Hypoxia组给予等量生理盐水;Hypoxia组和HL组进行模拟海拔5000 m低压低氧处理6 h,NC组和LPS组于舱外同时饲养。检测肺组织的湿/干质量比(wet/dry mass ratio,WDR)、支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)蛋白含量,HE染色观察肺组织病理改变。提取肺组织总RNA,采用Affymetrix基因芯片检测mRNA表达谱,采用Metascape在线基因注释和分析系统(http://metascape.org)对差异表达基因进行基因本体论(gene ontology,GO)和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)信号通路聚类分析。结果HL组大鼠肺组织表现出明显的充血、水肿、肺泡间隔增宽。与NC组比较,HL组大鼠肺WDR显著增加(P<0.01),BALF蛋白含量显著升高(P<0.05)。基因表达检测发现,相对NC组,Hypoxia组有79个基因表达上调,59个基因表达下调,LPS组473个基因表达上调,695个基因表达下调,HL组669个基因表达上调,1253个基因表达下调。GO和KEGG信号通路聚类分析显示:HL组差异表达上调基因主要富集于细胞因子介导的信号通路、对IL-1的反应、炎症反应调节等生物学过程,以及细胞因子-细胞因子受体相互作用、TNF、NF-κB、IL-17、补体和凝血级联反应等信号通路;表达下调的基因主要富集到细胞外基质组织、内皮细胞迁移调控、细胞-基质黏附等生物学过程,以及黏着斑、Wnt、cGMP-PKG、PI3K-Akt、Rap1等信号通路。HL组大鼠肺组织中NF-κB、TNF-α、IL-1β以及IL-6的mRNA表达均显著上调(P<0.01)。结论低氧复合低剂量LPS可稳定复制大鼠HAPE模型,低氧可显著增强LPS诱导的炎症、免疫反应,显著增强炎症介质的表达,促进HAPE的发生发展。 展开更多
关键词 高原肺水肿 低氧 基因表达谱 基因芯片
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沉香历代香谱考证和香气成分研究进展
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作者 董文化 王昊 +6 位作者 李薇 曾军 黄圣卓 王雅丽 云翠鸿 梅文莉 戴好富 《香料香精化妆品》 CAS 2024年第3期1-16,共16页
香气是评价沉香品质的重要指标,沉香因其独特的香气被誉为四大名香之首(沉、檀、龙、麝)。目前,国内外学者已经对沉香的化学成分进行了大量报道,主要包括倍半萜类、2-(2-苯乙基)色酮类和芳香族类成分。然而,对于沉香的香气成分和香气特... 香气是评价沉香品质的重要指标,沉香因其独特的香气被誉为四大名香之首(沉、檀、龙、麝)。目前,国内外学者已经对沉香的化学成分进行了大量报道,主要包括倍半萜类、2-(2-苯乙基)色酮类和芳香族类成分。然而,对于沉香的香气成分和香气特征缺乏系统的分析和总结。本文旨在综述沉香的历代香谱考证和香气成分的现代研究,并初步构建沉香的香气轮廓图,同时展望沉香后续的分子感官研究,以期揭示沉香致香的奥秘。 展开更多
关键词 沉香 香气成分 香气特征 香气轮廓 研究进展
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体散射函数及衰减系数快速剖面仪的研发及应用
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作者 李彩 刘聪 +6 位作者 张现清 陈飞 肖志会 杨泽明 郑媛宁 周雯 许占堂 《热带海洋学报》 CAS CSCD 北大核心 2024年第2期1-11,共11页
水体体散射函数(volume scattering function, VSF,β(θ,λ))、吸收系数a(λ)及衰减系数c(λ)是海水固有光学特性的基础性参数,基于上述参数可以进一步推算得到水体所有特征性光学特性参数,进而为海洋初级生产力、全球碳循环等基础和... 水体体散射函数(volume scattering function, VSF,β(θ,λ))、吸收系数a(λ)及衰减系数c(λ)是海水固有光学特性的基础性参数,基于上述参数可以进一步推算得到水体所有特征性光学特性参数,进而为海洋初级生产力、全球碳循环等基础和前端领域研究以及水色遥感、水环境监测及灾害预警、水下光场分布、目标追踪、光伏发电等军民融合领域的应用和发展提供重要的数据支撑。受限于体散射函数的强方向性,其测量技术难度大且发展不成熟。文章以高角度分辨率多角度体散射函数及衰减系数高频剖面测量为目标,研发了可同步获取17个角度体散射函数、水体衰减系数、剖面深度及温度信息的快速剖面测量仪(volume scattering and attenuation meter,VSAM),其测量频率最高可达20Hz,体散射函数测量角度范围为10°~170°,角度分辨率10°,剖面最大工作深度200m。利用VSAM对三亚湾和崖州湾水体光学特性分布进行剖面调查研究:整体上,崖州湾和三亚湾水体体散射函数及衰减系数均存在较大的水平、垂直及角度(体散射函数)变化特征;同一水层,自西向东衰减及体散射函数呈递减趋势;同一站位,衰减及体散射函数随剖面深度呈递增趋势;前向10°体散射函数最大,后向120°体散射函数最小,前后向体散射函数相差2个数量级甚至更高。结合同期获取的水体浊度和叶绿素浓度剖面调查结果发现,浊度是崖州湾水体体散射函数及衰减系数显著高于三亚湾的主导贡献者,且上述海域水体浊度与颗粒物散射βp(90°, 650)及衰减cp(6 50)具有很好的线性相关性。VSAM测得的衰减系数及后向体散射函数分别与Viper(Trios公司,德国)及ECO-VSF3 (Seabird公司,美国)测量结果在剖面分布上具有较好的一致性。 展开更多
关键词 体散射函数 衰减系数 剖面测量 三亚湾 崖州湾
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基于圆弧刀补偿加工的平面调制切削技术研究
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作者 童维超 蒋柏斌 +4 位作者 吴小军 李国 黄燕华 张春雨 马小军 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期121-126,共6页
针对尖刀加工的平面调制微结构表面质量差以及尖刀顶部尖角易磨损的现象,本文系统分析了尖刀在加工平面调制结构时轮廓误差的形成机理,发现了尖刀加工调制表面的轮廓误差大且存在难以补偿的特性,调制结构的轮廓误差与刀尖宽度成正比,与... 针对尖刀加工的平面调制微结构表面质量差以及尖刀顶部尖角易磨损的现象,本文系统分析了尖刀在加工平面调制结构时轮廓误差的形成机理,发现了尖刀加工调制表面的轮廓误差大且存在难以补偿的特性,调制结构的轮廓误差与刀尖宽度成正比,与调制的周幅比值(λ/a)成反比.为此,本文提出了采用圆弧刀具结合刀具半径补偿方法以降低平面调制样品轮廓误差的技术方案.实验结果表明,采用圆弧刀结合刀具补偿方法对平面调制结构的轮廓精度提升具有显著作用,相比于尖刀切削,圆弧刀补偿加工的一维调制样品获得了更高的表面质量和轮廓精度.针对幅值a=4μm,周期λ=60μm的平面调制样品,采用圆弧刀补偿加工方案,调制样品的表面粗糙度Ra值由59.66 nm降至21 nm,轮廓误差精度提高了约20%. 展开更多
关键词 平面调制结构 轮廓误差 周幅比值(λ/a) 圆弧刀 半径补偿 表面粗糙度
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