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不同采样期党参炔苷的含量动态变化分析 被引量:4
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作者 马琴国 安培坤 王引权 《西部中医药》 2014年第2期23-25,共3页
目的:分析不同采样期党参炔苷的含量。方法:炔苷含量采用高效液相色谱分析,TC-C18色谱柱(4.6 mm&#215;250 mm,5μm),以乙腈-水(22∶78)为流动相,流速:1.0 mL/min。检测波长267 nm,柱温25℃。结果:党参炔苷在1.12~0.80μg... 目的:分析不同采样期党参炔苷的含量。方法:炔苷含量采用高效液相色谱分析,TC-C18色谱柱(4.6 mm&#215;250 mm,5μm),以乙腈-水(22∶78)为流动相,流速:1.0 mL/min。检测波长267 nm,柱温25℃。结果:党参炔苷在1.12~0.80μg/mL范围内呈良好的线性关系,r=0.9996,精密度RSD为1.28%(n=6),重复性RSD为1.9%,平均回收率为99.50%,RSD为1.90%(n=6),测定了不同采收期党参中党参炔苷的含量范围为0.87~3.00 mg/g。结论:分析了不同采样期党参炔苷的含量,为党参规范化栽培提供参考。 展开更多
关键词 不同采样期 党参 党参炔苷 高效液相
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牧草ADF与NDF随采样期变化的研究 被引量:1
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作者 赵毅牢 刘亚明 刘小牛 《内蒙古畜牧科学》 2000年第4期41-42,共2页
关键词 牧草 粗纤维含量 ADF NDF 采样期
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采样时间对赤霉素处理杜仲叶次生代谢物含量的影响 被引量:7
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作者 张强 苏印泉 徐咏梅 《西北林学院学报》 CSCD 北大核心 2010年第6期130-133,共4页
为研究采样时间对赤霉素处理杜仲叶中次生代谢物含量的影响,采用喷施法,以2a生杜仲幼苗为试验材料,测定了不同采样期赤霉素处理杜仲叶中京尼平苷酸、桃叶珊瑚苷、绿原酸和总黄酮含量。结果表明:采样时间对赤霉素处理杜仲叶中京尼平苷酸... 为研究采样时间对赤霉素处理杜仲叶中次生代谢物含量的影响,采用喷施法,以2a生杜仲幼苗为试验材料,测定了不同采样期赤霉素处理杜仲叶中京尼平苷酸、桃叶珊瑚苷、绿原酸和总黄酮含量。结果表明:采样时间对赤霉素处理杜仲叶中京尼平苷酸、桃叶珊瑚苷、绿原酸和总黄酮含量有显著影响。在试验期内,所有采样时间赤霉素均可以提高杜仲叶京尼平苷酸含量,且大多数采样时间赤霉素处理提高了桃叶珊瑚苷和绿原酸含量,但赤霉素处理在所有采样时间均降低总黄酮含量。在试验期内,赤霉素处理对杜仲叶总黄酮含量变化影响较明显,对京尼平苷酸含量变化影响较小。 展开更多
关键词 杜仲 赤霉素 采样期 次生代谢物
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环境医学
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《环境工程技术学报》 CAS 2003年第5期21-22,共2页
关键词 环境医学 二氧化氮 采样期 平均浓度 原生 环图 杀虫剂 墨西哥城 除虫菊 雌性激素
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Phenotypic correlations of somatic and gonad traits of sea urchins Glyptocidaris crenularis in two sampled periods:first insight into its breeding and aquaculture 被引量:3
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作者 罗世滨 田晓飞 +4 位作者 赵冲 周海森 张伟杰 封文萍 常亚青 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期344-348,共5页
Prior knowledge of the correlations among commercially important traits in Glyptocidaris crenularis can be used to guide development of breeding and aquaculture programs for this species.We evaluated the phenotypic co... Prior knowledge of the correlations among commercially important traits in Glyptocidaris crenularis can be used to guide development of breeding and aquaculture programs for this species.We evaluated the phenotypic correlations between somatic and gonadal traits in G.crenularis during two sample periods(October 2010 and April 2011).The coeffi cients of variation(CV%)for body weight(BW),redness(a*),yellowness(b*),gonad wet weight(GW),and gonad index(GI)were>20% in both periods,while those of other traits were very low.GW was signifi cantly correlated with somatic traits(diameter,height,and body weight)in both periods,although the correlation coeffi cients ranged from 0.473 to 0.636(P<0.01).Gonad moisture content(GC),a*,and lightness(L*)were not signifi cantly correlated with somatic traits(P>0.05).The color trait b* was negatively correlated with somatic traits(test diameter,test height,and body weight)during the period when the gonads were well developed(April 2011,P<0.05).We observed little difference in the nature of the phenotypic correlations between the two sample periods.The high variation in the somatic and gonad weight traits in G.crenularis suggests there is considerable potential for selective breeding.However,our results suggest that gonad quality traits cannot be selected indirectly by selecting for body weight.Our study provides an insight into the method for improving the breeding and aquaculture of G.crenulari. 展开更多
关键词 Glyptocidaris crenularis GONAD phenotypic correlations indirect selection
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Life prediction and test period optimization research based on small sample reliability test of hydraulic pumps 被引量:5
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作者 郭锐 Ning Chao +4 位作者 Zhao Jingyi Wang Ping Shi Yu Zhou Jinsheng Luo Jing 《High Technology Letters》 EI CAS 2017年第1期63-70,共8页
Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-savi... Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-saving and power recovery,a small sample hydraulic pump reliability test rig is built,and the service life of hydraulic pump is predicted,and then the sampling period of reliability test is optimized. On the basis of considering the performance degradation mechanism of hydraulic pump,the feature information of degradation distribution of hydraulic pump volumetric efficiency during the test is collected,so an optimal degradation path model of feature information is selected from the aspect of fitting accuracy,and pseudo life data are obtained. Then a small sample reliability test of period constrained optimization search strategy for hydraulic pump is constructed to solve the optimization problem of the test sampling period and tightening end threshold,and it is verified that the accuracy of the minimum sampling period by the non-parametric hypothes is tested. Simulation result shows it could possess instructional significance and referenced value for hydraulic pump reliability life evaluation and the test's research and design. 展开更多
关键词 hydraulic pump small sample test volumetric efficiency degradation path model life span period optimal
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Mobile robot path planning method combined improved artificial potential field with optimization algorithm 被引量:1
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作者 赵杰 Yu Zhenzhong Yan Jihong Gao Yongsheng Chen Zhifeng 《High Technology Letters》 EI CAS 2011年第2期160-165,共6页
To overcome the shortcomings of the traditional artificial potential field method in mobile robot path planning, an improved artificial potential field model (IAPFM) was established, then a new path planning method ... To overcome the shortcomings of the traditional artificial potential field method in mobile robot path planning, an improved artificial potential field model (IAPFM) was established, then a new path planning method combining the IAPFM with optimization algorithm (trust region algorithm) is proposed. Attractive force between the robot and the target location, and repulsive force between the robot and the obstacles are both converted to the potential field intensity; and filled potential field is used to guide the robot to go out of the local minimum points ; on this basis, the effect of dynamic obstacles velocity and the robot's velocity is consid thers and the IAPFM is established, then both the expressions of the attractive potential field and the repulsive potential field are obtained. The trust region algorithm is used to search the minimum value of the sum of all the potential field inten- sities within the movement scope which the robot can arrive in a sampling period. Connecting of all the points which hare the minimum intensity in every sampling period constitutes the global optimization path. Experiment result shows that the method can meet the real-time requirement, and is able to execute the mobile robot path planning task effectively in the dynamic environment. 展开更多
关键词 trust region optimization algorithm path planning artificial potential field mobile robot potential field intensity
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Rapid identification of single constant contaminant source by considering characteristics of real sensors
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作者 蔡浩 李先庭 +2 位作者 孔令娟 马晓钧 邵晓亮 《Journal of Central South University》 SCIE EI CAS 2012年第3期593-599,共7页
For the release of hazardous contaminant indoors, source identification is critical for developing effective response measures. A method which can quickly and accurately identify the position, emission rate, and relea... For the release of hazardous contaminant indoors, source identification is critical for developing effective response measures. A method which can quickly and accurately identify the position, emission rate, and release time of a single constant contaminant source by using real sensors was presented. The method was numerically demonstrated and validated by a case study of contaminant release in a three-dimensional office. The effects of the measurement errors and total sampling period of sensor on the performance of source identification were thoroughly studied. The results indicate that the adverse effects of the measurement errors can be mitigated by extending the total sampling period. For reaching a desirable accuracy of source identification, the total sampling period should exceed a certain threshold, which can be determined by repeatedly running the identification method tmtil the results tend to be stable. The method presented can contribute to develop an onsite source identification system for protecting occupants from indoor releases. 展开更多
关键词 source identification contaminant source indoor environment computational fluid dynamics (CFD) air distribution
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Investigation Food Diet of Cobitis taenia in Talar River (Mazandaran Province)
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作者 Soheil Bahrebar 《Journal of Food Science and Engineering》 2012年第12期697-704,共8页
Perch sweeper fish with scientific name Cobitis taenia is one of the Cobitidae family. Since this kind of fish lives in clean waters and in the high areas of Talar River, it can be an index on water implution. This su... Perch sweeper fish with scientific name Cobitis taenia is one of the Cobitidae family. Since this kind of fish lives in clean waters and in the high areas of Talar River, it can be an index on water implution. This survey on the diet of this specimen is done on two stations (Kaselian and Tajoon) and shallow and high areas of Talar River in Mazandaran (Southern part of Caspian sea) and the duration of this survey is from October 2008 till September 2009. We should mention that fishing was just done by electro-shocker with voltage 300 V. And this fish after fishing is fixation in 10% formalin solution. So 410 perch sweeper fish were examined and the average of relatively length of gut (RLG) was 17.35 cm. The index of vacated intestine (VI) was calculated 43.35% for all samples. From intense of diet points of view (GSI), the most frequency of full intestines was considered in summer and spring. On the other hand, the smallness of relatively length of gut index (RLG 〈 1) shows that perch sweeper fish's diet manner is inclined to herbivority. In the examination of containing of digestive track, overally 10 kinds of foodstuff were known. Based on amount of this index, 2.67% Chironomidae is known as main bait in all sampling period. 展开更多
关键词 Perch sweeper fish (Cobitis taenia) DIET Mazandaran Talar River.
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Chinese Business Cycles Identified by Coincident Indexes
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作者 汪红驹 张慧莲 《China Economist》 2014年第1期110-124,共15页
In reference to the method of the Conference Board,the coincident indexes for China are constructed from a sample period between January 1990 and May 2012 and by51 chosen component indicators.The resulting coincident ... In reference to the method of the Conference Board,the coincident indexes for China are constructed from a sample period between January 1990 and May 2012 and by51 chosen component indicators.The resulting coincident indexes have higher correlations with gross domestic product(GDP) growth rates than the China Economic Monitoring and Analysis Center(CEMAC) coincident index over the sample period between February2005 and May 2012.The peaks and troughs of the growth rates in several indicators are identified.The total number of peaks and troughs in the resulting coincident index is the same with the CEMAC coincident index.Unfortunately,these troughs don't signify recessions in the Chinese economy because the financial system has not seen a negative growth rate over the specific sample periods.The impacts of the Southeast Asian Financial Crisis and subprime mortgage crisis on the business cycle could be dated via a smoother index from HP filtering to the coincident index. 展开更多
关键词 coincident index business cycle Bry-Boschan algorithm
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Removal of Dominant Adrenal Lateralized by Glucagon-Stimulated Adrenal Venous Sampling Alleviates Hypertension in Bilateral Pheochromocytoma
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作者 Chandy Lou P. Malong Mary Jane Tanchee-Ngo +2 位作者 Pilar Torres-Salvador Karel Pacak Leilani B.Mercado-Asis 《Journal of Life Sciences》 2013年第6期586-591,共6页
In bilateral pbeochromocytoma, localization of the dominant adrenal is challenging but highly important since the removal of dominant side can markedly improve cardiovascular outcomes. To demonstrate the usefulness of... In bilateral pbeochromocytoma, localization of the dominant adrenal is challenging but highly important since the removal of dominant side can markedly improve cardiovascular outcomes. To demonstrate the usefulness of glucagon-stimulated BAVS (bilateral adrenal venous sampling) in determining the dominant adrenal to be removed, the authors reviewed records of patients who underwent BAVS with glucagon stimulation from 1997-2010. Nineteen out of 44 patients were diagnosed with bilateral pheochromocytoma. Mean age at diagnosis was 33 ± 14 years. Duration of hypertension was 5 ± 6 years with highest systolic BP (blood pressure) of 186 ±30 mmHg and diastolic BP of 113 ±18 mmHg. Headache (68%) is the most common symptom followed by paroxysmal hypertension (58%). Majority were taking 〉 3 anti-hypertensive drugs. On glucagon-stimulated BAVS, 63% had right adrenal dominance. Three patients, who were hypertensive for 1, 6 and 12 years, underwent removal of the dominant adrenal. On follow-up (mean period = 36 months), there was marked improvement in BP control [pre-op vs. post-op: (systolic) 160-240 mmHg vs. 120-150 mmHg; (diastolic) 90-110 mmHg vs. 70-90 mmHg] and reduction in number of anti-hypertensive medications (from 3-5 to 2 classes of drugs). BAVS with glucagon stimulation is a valuable tool in the identification of the dominant adrenal to be removed in patients with bilateral pheochromocytoma to alleviate chronic hypertension. 展开更多
关键词 Adrenal sampling endocrine hypertension bilateral pheochromocytoma neuroendocrine tumor adrenalectomy.
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CMOS图像传感器中数字噪声抑制技术研究 被引量:7
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作者 刘洪文 张生才 +1 位作者 姚素英 徐江涛 《光电子.激光》 EI CAS CSCD 北大核心 2007年第4期411-413,共3页
设计了一种可以降低CMOS图像传感器(CIS)中数字噪声对模拟信号影响的时序。在时序控制电路中加入了门控时钟,使数字电路各模块可分时工作,在模拟电路采样阶段保持静止以抑制噪声。理论分析和测试结果表明,采样阶段噪声减小70%,其他时间... 设计了一种可以降低CMOS图像传感器(CIS)中数字噪声对模拟信号影响的时序。在时序控制电路中加入了门控时钟,使数字电路各模块可分时工作,在模拟电路采样阶段保持静止以抑制噪声。理论分析和测试结果表明,采样阶段噪声减小70%,其他时间噪声减小20%。 展开更多
关键词 CMOS图像传感器(CIS) 数字噪声 时序 静止采样
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