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Process Parameters Optimization of Laser Cladding for HT200 with 316L Coating Based on Response Surface Method
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作者 KONG Huaye ZHU Xijing +2 位作者 LI Zejun ZHANG Jinzhe LI Zuoxiu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1569-1579,共11页
In order to improve the sealing surface performance of gray cast iron gas gate valves and achieve precise molding control of the cladding layer,as well as to reveal the influence of laser cladding process parameters o... In order to improve the sealing surface performance of gray cast iron gas gate valves and achieve precise molding control of the cladding layer,as well as to reveal the influence of laser cladding process parameters on the morphology and structure of the cladding layer,we prepared the 316L coating on HT 200 by using Design-Expert software central composite design(CCD)based on response surface analysis.We built a regression prediction model and analyzed the ANOVA with the inspection results.With a target cladding layer width of 3.5 mm and height of 1.3 mm,the process parameters were optimized to obtain the best combination of process parameters.The microstructure,phases,and hardness variations of the cladding layer from experiments with optimal parameters were analyzed by the metallographic microscope,confocal microscope,and microhardness instrument.The experimental results indicate that laser power has a significant impact on the cladding layer width,followed by powder feed rate;scan speed has a significant impact on the cladding layer height,followed by powder feed rate.The HT200 substrate and 316L can metallurgically bond well,and the cladding layer structure consists of dendritic crystals,columnar crystals,and equiaxed crystals in sequence.The optimal process parameter combination satisfying the morphology requirements is laser power(A)of 1993 W,scan speed(B)of 8.949 mm/s,powder feed rate(C)of 1.408 r/min,with a maximum hardness of 1564.3 HV0.5,significantly higher than the hardness of the HT200 substrate. 展开更多
关键词 HT200 laser cladding 316l stainless steel response surface methodology process parameter optimization
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钢筋混凝土不等肢L形单向偏心受压柱参数分析
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作者 朱思静 刘俊 陈叶 《价值工程》 2024年第23期112-115,共4页
本文运用了ABAQUS有限元软件,设计了14个有限元试件进行参数分析,具体分析了钢筋混凝土不等肢L形单向偏心受压柱的承载力及变形能力受混凝土强度、纵筋配筋率、偏心率等因素的影响规律。
关键词 钢筋混凝土不等肢l形柱 单向偏心 有限元分析 参数分析
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日粮中添加l-精氨酸对公犬精液品质、生殖器超声参数及血清睾酮的影响
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作者 修福晓 于广波 +4 位作者 杨宇翔 王东伟 孙宁 刘成武 王朋朋 《黑龙江畜牧兽医》 CAS 北大核心 2024年第6期115-120,共6页
为了探究日粮中添加l-精氨酸对公犬精液品质、生殖器超声参数及血清睾酮的影响,试验从沈阳市某警犬基地选取体重相近的4~5岁健康史宾格公犬20只,随机分为4组(n=5),分别为试验A组、试验B组、试验C组和对照组,试验A组、试验B组和试验C组... 为了探究日粮中添加l-精氨酸对公犬精液品质、生殖器超声参数及血清睾酮的影响,试验从沈阳市某警犬基地选取体重相近的4~5岁健康史宾格公犬20只,随机分为4组(n=5),分别为试验A组、试验B组、试验C组和对照组,试验A组、试验B组和试验C组分别按体重每天在日粮中添加10,15,20 mg/kg l-精氨酸,对照组日粮中不添加l-精氨酸,试验期为30 d。于试验第1,10,20,30天分别对各组的精液品质(精液量、精液、密度精子、活力精子活率)、生殖器超声参数(睾丸宽度、睾丸深度和附睾尾部厚度)及血清睾酮质量浓度进行检测。结果表明:试验第1,10天,各指标各组间均差异不显著(P>0.05)。试验第20天,试验A组、试验B组和试验C组的精液密度、精子活力显著高于对照组(P<0.05),试验B组的精液密度显著高于试验A组和试验C组(P<0.05);试验B组和试验C组左右两侧睾丸宽度和睾丸深度显著高于对照组和试验A组(P<0.05)。试验第30天,试验A组、试验B组和试验C组的精液密度、精子活力显著高于对照组(P<0.05),试验B组的精液密度和精子活力显著高于试验A组和试验C组(P<0.05),试验C组的精液密度显著高于试验A组(P<0.05);试验B组和试验C组左右两侧睾丸宽度、睾丸深度和附睾尾部厚度显著高于对照组和试验A组(P<0.05);试验B组和试验C组的血清睾酮质量浓度显著高于对照组和试验A组(P<0.05)。说明日粮中添加适量l-精氨酸可提高公犬的精液品质、生殖器超声参数和血清睾酮质量浓度;在本试验条件下按体重每天添加15 mg/kg l-精氨酸的效果最好。 展开更多
关键词 l-精氨酸 精液品质 生殖器超声参数 血清睾酮
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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass Composition l1 regularization logistic regression Model K-Means Clustering Analysis Elbow rule parameter Verification
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L-Arginine Supplementation Mitigates Dichlorvos-Induced Haematocardiotoxicity, and Oxidative Stress in Male Wistar Rats
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作者 Waidi Adeoye Saka Yusuff Dimeji Igbayilola +6 位作者 Jabba Hamidu Lawan Taoheed Kolawole Muftaudeen Ridwanullahi Adejumo Tolulope Deborah Alu Mary Ikuomola Joshua Tinuade Ojelere Victor Odufa Adegoke 《Open Journal of Applied Sciences》 2024年第7期1886-1903,共18页
Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementat... Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementation against dichlorvos-induced toxicity, focusing on cardiotoxicity, haematotoxicity and oxidative stress. The rats were divided into four groups: Control, L-arginine (L), Dichlorvos (D), and L-arginine + Dichlorvos (L + D). Dichlorvos was administered to the D group, L-arginine (100 mg/kg) to the L group, and both L-arginine and dichlorvos to the L + D group. The study evaluated various parameters, including cardiovascular, oxidative stress markers, and haematological indices. Significant changes in haematological parameters such as haemoglobin (Hb), haematocrit (HCT), and red blood cell count (RBC) indicated haematotoxicity after dichlorvos administration. Additionally, elevated cardiac markers, including lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB), suggested cardiotoxic effects. Exposure to dichlorvos also resulted in decreased antioxidant enzyme levels and increased oxidative stress indicators like malondialdehyde (MDA). Remarkably, L-arginine supplementation mitigated the damage caused by dichlorvos. It normalized the altered haematological parameters, demonstrating its protective effect against haematotoxicity. The rise in cardiac markers was reduced with L-arginine supplementation, indicating protection against cardiotoxicity. Moreover, L-arginine significantly decreased oxidative stress, as evidenced by lower MDA levels and restored antioxidant enzyme activity. In conclusion, L-arginine supplementation in male Wistar rats showed promising protective effects against dichlorvos-induced cardiotoxicity, haematotoxicity and oxidative stress. This suggests that L-arginine may offer a beneficial intervention to mitigate the adverse effects of dichlorvos on blood and heart health, paving the way for potential treatments for pesticide poisoning. 展开更多
关键词 DICHlOrVOS l-ArGININE Cardiovascular Function Haematological parameters Oxidative Stress
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复杂载荷下含缺陷管道的极限载荷及L_r参量
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作者 郭茶秀 魏新利 +1 位作者 王定标 刘宏 《郑州大学学报(工学版)》 CAS 2004年第1期49-52,93,共5页
基于净截面垮塌准则(NSC)和Von-Mises屈服准则,推导了空间含缺陷管道在拉伸、弯曲、扭矩和内压多种载荷共同作用下的塑性极限载荷方程.另外还给出了在三维应力状态下的含缺陷结构Lr参量的新定义,针对多载荷作用下的周向裂纹管提出了求... 基于净截面垮塌准则(NSC)和Von-Mises屈服准则,推导了空间含缺陷管道在拉伸、弯曲、扭矩和内压多种载荷共同作用下的塑性极限载荷方程.另外还给出了在三维应力状态下的含缺陷结构Lr参量的新定义,针对多载荷作用下的周向裂纹管提出了求解Lr参量的联立方程法、幂指数法.补充和完善了现有规范,对含缺陷结构的失效评定工作具有重要的意义. 展开更多
关键词 塑性极限载荷 裂纹管 lr参量 含缺陷管道 管线
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2021-09-29宁夏中宁M_(L)3.6地震震源参数测定 被引量:1
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作者 许英才 曾宪伟 《大地测量与地球动力学》 CSCD 北大核心 2023年第2期215-220,共6页
基于宁夏区域地震台网资料,采用初至P震相定位法测定2021-09-29中宁M_(L)3.6地震震源深度,同时利用gCAP反演方法测定该地震震源机制解及矩张量解,然后根据震源机制与应力场模拟方法计算现今应力场体系在中宁M_(L)3.6地震震源机制两个节... 基于宁夏区域地震台网资料,采用初至P震相定位法测定2021-09-29中宁M_(L)3.6地震震源深度,同时利用gCAP反演方法测定该地震震源机制解及矩张量解,然后根据震源机制与应力场模拟方法计算现今应力场体系在中宁M_(L)3.6地震震源机制两个节面的相对剪应力和正应力。结果表明,初至P震相定位法和gCAP方法测定的中宁M_(L)3.6地震震源深度均为11 km,震源机制节面Ⅰ走向242°、倾角63°、滑动角8°,节面Ⅱ走向148°、倾角83°、滑动角153°,矩张量解结果表明该地震的双力偶成分占全矩张量解的97.07%,表明该地震为天然地震。结合震中附近2009年以来M_(L)1.0以上地震重定位后的空间分布、区域地质构造和相对剪应力等分析推测,中宁M_(L)3.6地震发震断层可能与天景山断裂东南段附近NNW向断裂薄弱带有关,该地震是在青藏高原东北缘NE向挤压作用下,沿着NNW向断裂剪切滑动引起的一次右旋走滑型地震事件。 展开更多
关键词 中宁M_(l)3.6地震 初至P震相定位法 gCAP方法 震源参数
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Evaluation of Chlorophyll Content and Fluorescence Parameters as Indicators of Drought Tolerance in Barley 被引量:53
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作者 LI Rong-hua GUO Pei-guo +2 位作者 Michael Baum Stefania Grando Salvatore Ceccarelli 《Agricultural Sciences in China》 CAS CSCD 2006年第10期751-757,共7页
Drought is a major abiotic stress that severely affects food production worldwide. Agronomic and physiological traits associated with drought tolerance are suitable indicators for selection of drought tolerance genoty... Drought is a major abiotic stress that severely affects food production worldwide. Agronomic and physiological traits associated with drought tolerance are suitable indicators for selection of drought tolerance genotypes to reduce the impact of water deficit on crop yield in breeding program. The objective of this study was to identify indicators related to drought tolerance through analysis of photosynthetic traits in barley (Hordeum vulgare L.). These traits included chlorophyll content, initial fluorescence (Fo), maximum primary yield of photochemistry of photosystem Ⅱ (Fv /Fo) and maximum quantum yield of photosystem Ⅱ (Fv/Fm). Four genotypes (Tadmor, Arta, Morocco9-75 and WI2291) variable in drought tolerance were used to investigate the correlation between these traits and drought tolerance. The results reflected that all of these traits were affected negatively in the four genotypes at different levels of post-anthesis drought stress, but the decrease in drought tolerant genotypes was much less than that of drought sensitive genotypes. The results further revealed that the components of the photosynthetic apparatus could be damaged significantly in drought sensitive genotypes, while drought tolerant genotypes were relatively less affected. On the other hand, the values of chlorophyll content, Fo, Fv/Fo and Fv/Fm in drought tolerance genotypes were significantly higher than those in drought sensitive genotypes under drought stress. It was concluded that chlorophyll content, Fo, Fv/Fo and Fv/Fm could be considered as reliable indicators in screening barley germplasm for drought tolerance. 展开更多
关键词 barley (Hordeum vulgare l.) CHlOrOPHYll chlorophyll fluorescence parameters drought tolerance
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Biomass-Based Rice (Oryza sativa L.) Aboveground Architectural Parameter Models 被引量:11
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作者 CAO Hong-xin LIU Yan +11 位作者 LIU Yong-xia Jim Scott Hanan YUE Yan-bin ZHU Da-wei LU Jian-fei SUN Jin-ying SHI Chun-lin GE Dao-kuo WEI Xiu-fang YAO An-qing TIAN Ping-ping BAO Tai-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第10期1621-1632,共12页
To quantify the relationships between rice plant architecture parameters and the corresponding organ biomass, and to research on functional structural plant models of rice plant, this paper presented a biomass-based m... To quantify the relationships between rice plant architecture parameters and the corresponding organ biomass, and to research on functional structural plant models of rice plant, this paper presented a biomass-based model of aboveground architectural parameters of rice (Oryza sativa L.) in the young seedling stage, designed to explain effects of cultivars and environmental conditions on rice aboveground morphogenesis at the individual leaf level. Various model variables, including biomass of blade and blade length, were parameterized for rice based on data derived from an outdoor experiment with rice cv. Liangyou 108, 86You 8, Nanjing 43, and Yangdao 6. The organ dimensions of rice aboveground were modelled taking corresponding organ biomass as an independent variable. Various variables in rice showed marked consistency in observation and simulation, suggesting possibilities for a general rice architectural model in the young seedling stage. Our descriptive model was suitable for our objective. However, they can set the stage for connection to physiological model via biomass and development of functional structural rice models (FSRM), and start with the localized production and partitioning of assimilates as affected by abiotic growth factors. The finding of biomass-based rice architectural parameter models also can be used in morphological models of blade, sheath, and tiller of the other stages in rice life. 展开更多
关键词 BIOMASS plant architectural parameter model rice (Oryza sativa l.)
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Application of response surface methodology to optimize process parameters in friction welding of Ti-6Al-4V and SS304L rods 被引量:3
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作者 R.KUMAR M.BALASUBRAMANIAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3625-3633,共9页
A method to decide near optimal settings of the process parameters in friction welding was proposed.The success of the friction welding process is based on various input parameters like friction pressure,friction time... A method to decide near optimal settings of the process parameters in friction welding was proposed.The success of the friction welding process is based on various input parameters like friction pressure,friction time,upset pressure and upset time and output parameters like tensile strength,hardness and material loss.Ti-6Al-4V and SS304L(SS) materials were joined by friction welding process using interlayer techniques.The Box-Behnken design and response surface methodology(RSM) were applied to deciding the number of experiments to be performed and identify the optimum process parameters for obtaining better joint strength.The results were highly encouraging.Join strength of 523 MPa was obtained at a friction pressure of 12 N/mm^2,upset pressure of40 N/mm^2,friction time of 1.2 s and upset time of 7 s. 展开更多
关键词 friction welding welding parameters TI-6Al-4V SS304l copper interlayer
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Quantifying the parameter dependent basin of the unsafe regime of asymmetric Lévy-noise-induced critical transitions 被引量:1
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作者 Jinzhong MA Yong XU +3 位作者 Yongge LI Ruilan TIAN Shao juan MA J.KURTHS 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第1期65-84,共20页
In real systems,the unpredictable jump changes of the random environment can induce the critical transitions(CTs)between two non-adjacent states,which are more catastrophic.Taking an asymmetric Lévy-noise-induced... In real systems,the unpredictable jump changes of the random environment can induce the critical transitions(CTs)between two non-adjacent states,which are more catastrophic.Taking an asymmetric Lévy-noise-induced tri-stable model with desirable,sub-desirable,and undesirable states as a prototype class of real systems,a prediction of the noise-induced CTs from the desirable state directly to the undesirable one is carried out.We first calculate the region that the current state of the given model is absorbed into the undesirable state based on the escape probability,which is named as the absorbed region.Then,a new concept of the parameter dependent basin of the unsafe regime(PDBUR)under the asymmetric Lévy noise is introduced.It is an efficient tool for approximately quantifying the ranges of the parameters,where the noise-induced CTs from the desirable state directly to the undesirable one may occur.More importantly,it may provide theoretical guidance for us to adopt some measures to avert a noise-induced catastrophic CT. 展开更多
关键词 tri-stable model asymmetric lévy noise critical transition(CT) escape probability absorbed region parameter dependent basin of unsafe regime(PDBUr)
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Parameter estimation for rigid body after micro-Doppler removal based on L-statistics in the radar analysis 被引量:2
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作者 Yong Wang Jian Kang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期457-467,共11页
In traditional inverse synthetic aperture radar (ISAR) imaging of moving targets with rotational parts, the micro-Doppler (m-D) effects caused by the rotational parts influence the quality of the radar images. Rec... In traditional inverse synthetic aperture radar (ISAR) imaging of moving targets with rotational parts, the micro-Doppler (m-D) effects caused by the rotational parts influence the quality of the radar images. Recently, L. Stankovic proposed an m-D removal method based on L-statistics, which has been proved effective and simple. The algorithm can extract the m-D effects according to different behaviors of signals induced by rotational parts and rigid bodies in time-frequency (T-F) domain. However, by removing m-D effects, some useful short time Fourier transform (STFT) samples of rigid bodies are also extracted, which induces the side lobe problem of rigid bodies. A parameter estimation method for rigid bodies after m-D removal is proposed, which can accurately re- cover rigid bodies and avoid the side lobe problem by only using m-D removal. Simulations are given to validate the effectiveness of the proposed method. 展开更多
关键词 parameter estimation l-STATISTICS micro-Doppler (m-D) radar imaging.
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基于K-L展开的断层-节理边坡随机有限元分析 被引量:2
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作者 杨洋 吴欣 刘文劼 《公路工程》 2023年第6期106-113,123,共9页
土性参数的空间变异性和断层-节理的耦合作用,将显著影响边坡工程的稳定性分析。基于K-L展开方法模拟土体抗剪强度参数空间变异性,同时通过强度折减法计算节理岩体边坡的稳定性系数,提出了一种考虑土体参数空间变异性的边坡可靠度分析... 土性参数的空间变异性和断层-节理的耦合作用,将显著影响边坡工程的稳定性分析。基于K-L展开方法模拟土体抗剪强度参数空间变异性,同时通过强度折减法计算节理岩体边坡的稳定性系数,提出了一种考虑土体参数空间变异性的边坡可靠度分析方法。探讨了土性参数的变异性及水平和垂直方向的相关距离对断层-节理边坡随机可靠度的影响。通过与已有研究中均质边坡稳定性对比分析,验证了模型的可行性,并结合现场实际工程进行分析。研究表明:断层-节理裂隙改变了边坡潜在滑移面产状,同时降低边坡的安全系数。边坡失效概率随着土性参数变异系数的增加而增大。忽略土性参数的变异性指标时,会高估边坡的安全系数指标,低估失效概率。土体竖向波动范围显著影响边坡的可靠度,断层-节理对于边坡稳定性的影响远大于土体波动范围。 展开更多
关键词 边坡工程 K-l展开 断层-节理边坡 随机有限元 参数变异性
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CONTINUITY OF l^2-VALUED TWO-PARAMETER ORNSTEIN UHLENBECK PROCESSES
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作者 Wen JiweiDept. of Math.,Zhejiang Univ.(Xixi Campus),Hangzhou 310028. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期423-429,共7页
Let {Y (t);t= (t 1,t 2)≥0}={X k(t 1,t 2);t 1≥0,t 2≥0} ∞ k=1 be a sequence of two parameter Ornstein Uhlenbeck processes (OUP 2) with coefficients α k>0,β k>0 . A Fernique type in... Let {Y (t);t= (t 1,t 2)≥0}={X k(t 1,t 2);t 1≥0,t 2≥0} ∞ k=1 be a sequence of two parameter Ornstein Uhlenbeck processes (OUP 2) with coefficients α k>0,β k>0 . A Fernique type inequality is established and the sufficient condition for a.s. l 2 continuity of Y(·) is studied by means of the inequality. 展开更多
关键词 l 2 valued two parameter Ornstein Uhlenbeck processes Fernique type inequality continuity.
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Effects of the Mixture of <i>Cichorium intybus</i>L. and <i>Cinnamomum zeylanicum</i>on Hepatic Enzymes Activity and Biochemical Parameters in Patients with Nonalcoholic Fatty Liver Disease
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作者 Zeynab Sheybani Asl Ali Akbar Malekirad +4 位作者 Mohammad Abdollahi Alireza Bakhshipour Hajar Akbari Dastjerdi Sara Mostafalou Razieh Yousef Poor 《Health》 2014年第11期1212-1217,共6页
The prevalence of nonalcoholic fatty liver disease (NAFLD) as a metabolic disorder affecting the liver function is rapidly increasing and there is a need to develop new and more efficient treatment. This study was des... The prevalence of nonalcoholic fatty liver disease (NAFLD) as a metabolic disorder affecting the liver function is rapidly increasing and there is a need to develop new and more efficient treatment. This study was designed to evaluate the protective effect of Cichorium intybus L. and Cinnamon mixture infusion (2.5 and 0.5 g/100mL and twice/day) on patients with NAFLD. This before-after clinical trial study was performed on 25 patients with NAFLD. They were administered the mixture of extract prepared in special bags twice a day for 30 days. Hepatic and metabolic markers of NAFLD like alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphates (ALP), fasting blood sugar (FBS), cholesterol (chol), triglycerides (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) in plasma and also, fatty liver ultrasonographic grading were determined before and after using the extracts. 30-day treatment with extracts in NAFLD patients resulted in a significant decrease in ALT and AST. FBS, TG and ALP were also decreased after administration of the extracts but not significantly. A significant linear correlation was found between age and ALP, and between gender and liver enzymes. It is concluded that the mixture of Cichorium intybus L. and Cinnamon extracts has some benefits in NAFLD patients making them valuable for future investigations. 展开更多
关键词 NONAlCOHOlIC Fatty lIVEr Disease CICHOrIUM intybus l. CINNAMON lIVEr Enzymes Biochemical parameters
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Parameter Optimization of Regularization Variational Merging and Its Application in GNSS/MET Water Vapor
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作者 Wang Gen Zhou Shuxue +1 位作者 Ding Xia Liu Huilan 《Meteorological and Environmental Research》 CAS 2019年第2期44-50,共7页
The paper discusses the core parameters of the 3 D and 4 D variational merging based on L1 norm regularization,namely optimization characteristic correlation length of background error covariance matrix and regulariza... The paper discusses the core parameters of the 3 D and 4 D variational merging based on L1 norm regularization,namely optimization characteristic correlation length of background error covariance matrix and regularization parameter. Classical 3 D/4 D variational merging is based on the theory that error follows Gaussian distribution. It involves the solution of the objective functional gradient in minimization iteration,which requires the data to have continuity and differentiability. Classic 3 D/4 D-dimensional variational merging method was extended,and L1 norm was used as the constraint coupling to the classical variational merged model. Experiment was carried out by using linear advection-diffusion equation as four-dimensional prediction model,and parameter optimization of this method is discussed. Considering the strong temporal and spatial variation of water vapor,this method is further applied to the precipitable water vapor( PWV) merging by calculating reanalysis data and GNSS retrieval.Parameters were adjusted gradually to analyze the influence of background field on the merging result,and the experiment results show that the mathematical algorithm adopted in this paper is feasible. 展开更多
关键词 VArIATIONAl MErGING l1 NOrM parameter optimization Precipitable water vapor rEGUlArIZATION parameter
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Impact of Composts Maturity on Growth and Agronomic Parameters of Maize (<i>Zea mays</i>)
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作者 Mawuli Tamakloe Edem Komi Koledzi +2 位作者 Etsè Aziable Maglwa Tcha-Thom Nitale M’Balikine Krou 《American Journal of Analytical Chemistry》 2021年第2期29-45,共17页
Several methods have been developed in the literature which allow the maturity of composts to be assessed before it is used in agriculture. The objective of this study is to assess the maturity of the composts produce... Several methods have been developed in the literature which allow the maturity of composts to be assessed before it is used in agriculture. The objective of this study is to assess the maturity of the composts produced at the platform of the NGO ENPRO in Lomé on the growth and agronomic parameters of maize (<i>Zea mays</i> L., var. IKENE). To do so, three types of compost (gargabe, fruit waste, animal litter) were made for at least 3 months. The chemical analysis, phytotoxicity and agronomic tests carried out made it possible to assess the maturity of these composts. Indeed, the evolution of the C/N ratio, of the electrical conductivity, the phytotoxicity tests and the growth parameters of the composts show that the composts N°1 and N°2 are mature at the end of the 3<sup>rd</sup> month of composting while the compost N°3 can only be considered mature at the end of the 5<sup>th</sup> month of composting. But, with a yield of 2.39 ± 0.28 t/ha and a mass of 1000 grains of 346 ± 4 g, the treatment at 5 t/ha of compost N°3, has the best agronomic parameters compared to other types of compost and treatment without organic amendment. These results also show that compost with a high electrical conductivity has an inhibitory effect on the growth of corn plants (<i>Zea mays</i> L., var. IKENE). Basic chemical analysis, phytotoxicity tests and height growth of maize (<i>Zea mays</i> L., var. IKENE) are relatively efficient methods for evaluating the maturity of composts. 展开更多
关键词 Compost Phytotoxicity Agronomic parameters GrOWTH Maize (Zea mays l. var. IKENE)
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Effects of Nitrogen Amount on the Photosynthesis Parameters of Summer Millet in North China
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作者 Qing ZHAO Guoshun ZHAO +2 位作者 Mengya YANG Susheng CHEN Kai XIAO 《Agricultural Biotechnology》 CAS 2018年第3期19-23,共5页
In this study,effects of nitrogen( N) amount applied on photosynthesis behaviors of the summer millet in North China was investigated. Photosynthetic rates( Pn),chlorophyll contents( Chl),photosynthetic active d... In this study,effects of nitrogen( N) amount applied on photosynthesis behaviors of the summer millet in North China was investigated. Photosynthetic rates( Pn),chlorophyll contents( Chl),photosynthetic active duration( PAD),and chlorophyll relative steady phase( RSP) in flag and the upper third leaves were assessed in cultivars of Baogu 19,Jigu 19,9050,and 60 D under three N treatments [i. e.,0( control),75,and 150 kg/hm2]. Results indicated that the photosynthesis parameters were drastically regulated by external N levels,all of them showing elevation along with the increased N input in both assayed leaves.Among the cultivars examined,behaviors of the photosynthetic parameters were much better in Baogu 19 and worse in 60 D. The plant yields in the cultivars under various N treatments were shown to be in consistent with the behavior of the photosynthesis parameters. Correlation analysis revealed that plant yield is positively correlated with Pn and Chl and significantly positively correlated with PAD and RSP,suggesting that longer effective photosynthetic duration of leaves impacts largely on plant biomass production and the yield formation potential. Our investigation indicates that suitable external N applied can increase the yield of summer millet associating with the improvement of photosynthesis behaviors in upper leaves that contribute to plant biomass at the late growth stage. Baogu 19 exhibited higher plant yield together with improved photosynthetic parameters in upper leaves,suggesting its potential as an elite cultivar in planting in the summer season of North China. 展开更多
关键词 Millet (Setaria italica l. Summer-sown eultivar N application level Photosynthesis parameter Plant productivity
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Evaluation of seed quality and oil parameters in native Iranian almond(Prunus L.spp.) species
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作者 Soghra Kiani Shakiba Rajabpoor +1 位作者 Karim Sorkheh Sezai Ercisli 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期115-122,共8页
We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds(Prunus L. spp.) accessions collected from different parts of Iran. There were significant differences in kerne... We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds(Prunus L. spp.) accessions collected from different parts of Iran. There were significant differences in kernel weight and oil parameters. Accessions ranged from0.20 to 1.5 g in kernel weight, 0.2–3.0 mm in shell thickness, and 16–55 % in oil content. The predominant vegetable oil components of kernels were 4.6–9.5 % palmitic acid, 0.4–0.8 % palmitoleic acid, 1.0–3.4 % stearic acid,48.8–88.4 % oleic acid and 11.3–33.2 % linoleic acid.Linolenic acid was detected in 15 accessions. High heritability was recorded for all studied traits and was maximum for shell thickness(98.5 %) and minimum for oil content(97.1 %). Maximum and minimum ‘Euclidean'pair wise dissimilarities were 17.9 and 0.5, respectively.All 40 accessions were grouped into two major clusters. 展开更多
关键词 Genetic diversity Kernel quality Oil parameters Wild almond(Prunus l.spp.)
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Robust L_1 filtering with pole constraint in a disk via parameter-dependent Lyapunov functions
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作者 LiYanhui WenQiyong +2 位作者 WangJunling WangChanghong GaoHuijun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期102-109,共8页
The problem of robust L 1 filtering with pole constraint in a disk for linear continuous polytopic uncertain systems is discussed. The attention is focused on design a linear asymptotically stable filter such that th... The problem of robust L 1 filtering with pole constraint in a disk for linear continuous polytopic uncertain systems is discussed. The attention is focused on design a linear asymptotically stable filter such that the filtering error system remains robustly stable, and has a L 1 performance constraint and pole constraint in a disk. The new robust L 1 performance criteria and regional pole placement condition are obtained via parameter-dependent Lyapunov functions method. Upon the proposed multiobjective performance criteria and by means of LMI technique, both full-order and reduced-order robust L 1 filter with suitable dynamic behavior can be obtained from the solution of convex optimization problems. Compared with earlier result in the quadratic framework, this approach turns out to be less conservative. The efficiency of the proposed technique is demonstrated by a numerical example. 展开更多
关键词 robust filtering parameter-dependent lyapunov function linear matrix inequality l 1 performance pole placement technique.
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