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1.
不同时期羊草群落光合速率与环境条件之间的关系模型   总被引:2,自引:1,他引:1  
利用1981-1985年间,内蒙古典型草原羊草群落光合速率和环境因子观测资料,按4个不同时期进行逐步多元回归,得到4个回归方程如下:1.6月上中旬植物生长初期,群落光合主要与光照强度和温度有关。其回归方程是y=-0.683+0.444x1-0.0391x+0.0742x3-0.00164x^23(式中y为羊草群我合速率gCo2/m^72.h,x1是光照强度10klx,x3为空气温度C)。方程的复相  相似文献   

2.
张文辉  祖元刚 《植物研究》1998,18(1):118-118
在不同生境条件下的固定样地内,观察分析了裂叶沙参种群的地上部分在一个生长季的生长过程和物侯特点。生长于灌木群落下,裂叶沙参地上部分生物量生长(y,g)与时间(x、d)的关系可以用公式:y=0.2872-0.0187x+0.0009x^2表示;地上各器官茎、叶、花枝、花芽、花和果的生物量(y,克)与生长时间(x,天)的关系可以用公式:y=b0+b1x+b2x^2表示。从4月10日到8月15日的速生期  相似文献   

3.
稀疏效应下Ⅲ型功能反应系统的定性分析   总被引:14,自引:0,他引:14  
本文对具稀疏效应和HollingⅢ型功能反应的食饵-捕食系统{x=x^2(b/s+x-a)(1+βx^2)-ax^2y,y=y(ωx^2-e)进行了定性分析,给出了唯一正平衡点全局渐近稳定的充分条件等一些定性性质的判别准则和生态意义,系统中正参数的变化是大范围的。  相似文献   

4.
影响禾谷缢管蚜种群密度的因子分析   总被引:1,自引:0,他引:1  
运用回归分析、通径分析和网络理论探讨了小麦植株体内氨基酸、蔗糖、水分和温度、光照等因子对禾谷缢管蚜种群量及其胚胎数的单个影响和综合作用。结果表明,单个因子对麦蚜的作用符合二次多项式y2=a+b1x+b2x^2或三次多项式y3=a+b1x+b2x^2+b3x^3关系,5个因子的共同作用以多元非线性回归模型y=a+ΣΣ(bijxi^j)+ΣΣ(bijxi'j'xi^jxi'^j')拟合比较合理。计算结  相似文献   

5.
刘二曼  印莉 《植物研究》1998,18(1):90-96
应用韭菜微核技术,检测哈尔滨市量具刃具厂含铬废水的遗传毒性,试验表明:含铬废水可诱导韭菜和蚕豆根尖细胞产生微核,进行回归分析,其蚕豆对Cr^+6诱变剂回归分析为y=24.94+127.77x(r=0.996,P〈0.01),韭菜对Cr^+6诱变剂回归广泛为:y=21.74+100.23x(r=0.900,P〈0.01),r=11.17+3.38x(r=0.781,P〈0.05),韭菜根尖微核技术具  相似文献   

6.
棉花体细胞再生过程中代谢物质变化规律的初探   总被引:4,自引:0,他引:4  
本文对诱导起始到胚分化整个过程中的愈伤组织的代谢物质进行生理生化分析,得到如下结果:1、可溶性糖和淀粉含量随着培养天数增加逐渐下降,下降趋势分别符合方程y=1.0572-0.0059x,y=2.342-0.0114x;2、蛋白质和核酸含量随着培养天数增加逐渐上升,上升趋势分别符合方程:y=0.261+0.0054x,y=0.329+0.0023x。  相似文献   

7.
可逆三分子反应模型的系统分析   总被引:6,自引:0,他引:6  
讨论了生化反应中一个可逆三分子反应的数学模型x=A-(B+1)x+x~2y-x~3;y=Bx-x~2y+x~3,应用常微分方程定性方法进行了分析。得到系统的一切正初值的正半轨线有界;当B<2A~2+1时系统不存在极限环;当B>2A~2 +1时系统存在唯一稳定的极限环.  相似文献   

8.
最大摄氧量(Vo2max)是评价人体体力的重要指标,其测定方法分直接法和间接法两种。目前所推导的间接计算公式都是在平原、或是在进入高原初期推导的,不适用于高原习服人群。本研究采用逐步回归的方法,推导出移居高原7-27个月、不同高度的青年男性Vo2max间接计算公式。在海拔3680m地区,Vo2max(L/min)=1.1531+0.007327身高(cm)+0.01613体重(kg)-0.005883晨脉(b/min)-0.004534运动心率(60W,6/min),R=0.745,P<0.01,SS=3.7799;或Vo2max(L/min)=1.2186+0.01984体重(kg)+0.07259肺活量(L)-0.006659晨脉(b/min),R=0.713,p<0.01,ss=3.9636。在4350m地区,Vo2.max(L/min)=0.4917+0.01687体重(kg)+0.1109肺活量(L)+0.001983屏气时间(S),R=0.781,P<0.01,SS=2.1356。计算值与实测值比较,变异系数在13%以内,结果准确可靠,适用于青年男性高原习服移居者。  相似文献   

9.
应用底物膜技术检测130例正常精液,精子顶体酶活性百分率的正常值下限为57%。459例不孕症病人精液分析,无精症25例,其余434例中75%精子顶体酶活性正常。实验表明精子密度对数值与顶体酶活性百分率之间有正相关,r=0.84(P<0.01),回归方程为顶体酶活性百分率y=48.43%+(8.9%)(log精子计数)。活动精子百分率与顶体酶活性之间有密切正相关,r=0.967,(P<0.01),顶体酶活性y=38.6%+0、36x%。前向活跃直线运动精子百分率与顶体酶活性之间也有密切相关.r=0.96,(P<0.01),顶体酶活性y=34.21%+0.61x%。  相似文献   

10.
桐粮间作林带的配置方式与农作物产量关系的研究   总被引:7,自引:0,他引:7  
吴刚  杨修 《生态学报》1998,18(2):167-170
以桐粮间作为例,研究了林带的不同配置结构、林带冠覆盖率及小麦产量之间的关系。结果表明,林带距(Xd)、小麦相对产量(Y)及间作年(A)之间的关系为:Y=90.3290-1.9982A+1.1924Xd-0.3349A^2+0.2910AXd-0.0032AXd^2;林带冠覆盖率(Xc)与小麦相对产量(Y)之间的关系为:Y=-0.046Xc^2+1.1539Xc+98.173(Xc≤28%),Y=e  相似文献   

11.
The BIOSTATOR Systems have an on-line glucose analyzer for use with whole blood. This analyzer utilizes a novel enzyme (glucose oxidase) membrane configuration and an electrochemical cell to measure the H2O2 generated. The analyzer response is fast, accurate, precise, stable, and linearly related to the blood glucose concentration over the full range of clinical interest. Extensive correlation studies have been completed to show the agreement between this analyzer and the U.S. Food and Drug Administration's recommended hexokinase-glucose-6-phosphate dehydrogenase procedure. In addition, studies on potentially interfering substance and the differences in whole blood and plasma glucose levels have been completed.  相似文献   

12.
The author modified a respiratory gas analyzer to analyze the respiratory 13CO2 of 12 small laboratory animals all at once. To investigate the practical use of this system, mice were orally (OR) or intravenously (i.v.) given glucose solutions containing three different amounts of 13C-labeled glucose. Expired 13CO2 derived from exogenous glucose was detected within 10 minutes after administration in OR mice, but about 30 minutes in i.v. mice. The height of the peak of 13CO2 expiration was correlated with the administered 13C-glucose mass.  相似文献   

13.
Summary A commercial glucose analyzer, originally designed for monitoring of blood glucose in patients, was tested for use in fermentation processes. The system operates in such a way that the measured value is updated every 90 seconds. The measuring range of the system is 0–5 g glucose/l and the accuracy is ±7%. The response time was found to be approximately 6 min. The system was used to follow fermentations with two different microorganisms, Saccharomyces cerevisiae and Escherichia coli in media containing up to 5 g/l of glucose. The performance was fully satisfactory and the values had a very good correlation with off-line analyses.  相似文献   

14.
The highly sensitive urine glucose meter based on amperometric glucose sensor was developed and commercialized. It shows remarkable performances of wide measurement range in 0-2000 mgdl(-1), rapid response time as 6s and robustness against influence by interferents like ascorbic acid or acetaminophen. Correlation between the developed urine glucose meter and commercialized clinical-use urine glucose analyzer showed excellent linear relationship. The monitoring of postmeal blood glucose levels by assess of urine glucose of actual subjects was performed with the developed urine glucose meter. The experimental results suggest the urine glucose level 120 min following the meal should be the appropriate index for diabetes or impaired glucose tolerance to control blood glucose level. The new portable meter was developed, and is expected for flexible use at places other than home or office.  相似文献   

15.
An off-line glucose analyzer, Yellow Springs Instrument (YSI) model 27 was modified and coupled to various peripheral components to produce a fast, fully automated system for the online determination of glucose concentration. The amount of time required to accomplish each measurement was in the order of two minutes. To demonstrate the utility of this system, various tests were performed. First, a stream containing known amounts of glucose was monitored on-line and the system was calibrated. The calibration curve was shown to be described by Michaelis-Menten kinetics. Once the system was properly calibrated, it was used to monitor the glucose concentration in the effluent stream of two different enzyme reactor systems. The glucose concentrations were within experimental error of those obtained via standard off-line techniques.  相似文献   

16.
Radiometric assays for glycerol, glucose, and glycogen   总被引:6,自引:0,他引:6  
We have developed radiometric assays for small quantities of glycerol, glucose and glycogen, based on a technique described by Thorner and Paulus (1971, J. Biol. Chem. 246, 3885-3894) for the measurement of glycerokinase activity. In the glycerol assay, glycerol is phosphorylated with [32P]ATP and glycerokinase, residual [32P]ATP is hydrolyzed by heating in acid, and free [32P]phosphate is removed by precipitation with ammonium molybdate and triethylamine. Standard dose-response curves were linear from 50 to 3000 pmol glycerol with less than 3% SD in triplicate measurements. Of the substances tested for interference, only dihydroxyacetone gave a slight false positive signal at high concentration. When used to measure glycerol concentrations in serum and in media from incubated adipose tissue, the radiometric glycerol assay correlated well with a commonly used spectrophotometric assay. The radiometric glucose assay is similar to the glycerol assay, except that glucokinase is used instead of glycerokinase. Dose response was linear from 5 to 3000 pmol glucose with less than 3% SD in triplicate measurements. Glucosamine and N-acetylglucosamine gave false positive signals when equimolar to glucose. When glucose concentrations in serum were measured, the radiometric glucose assay agreed well with hexokinase/glucose-6-phosphate dehydrogenase (H/GDH)-based and glucose oxidase/H2O2-based glucose assays. The radiometric method for glycogen measurement incorporates previously described isolation and digestion techniques, followed by the radiometric assay of free glucose. When used to measure glycogen in mouse epididymal fat pads, the radiometric glycogen assay correlated well with the H/GDH-based glycogen assay. All three radiometric assays offer several practical advantages over spectral assays.  相似文献   

17.
A glucose control system consisting of a single in-line glucose sensor, concentrated glucose solution, and computer hardware and software were developed. The system was applied to continuously control glucose concentrations of a perfusion medium in a rotating wall perfused vessel (RWPV) bioreactor culturing BHK-21 cells. The custom-made glucose sensor was based on a hydrogen peroxide electrode. The sensor continuously and accurately measured the glucose concentration of GTSF-2 medium in the RWPV bioreactor during cell culture. Three sets of two-point calibrations were applied to the glucose sensor during the 55-day cell culture. The system first controlled the glucose concentration in perfusing medium between 4.2 and 5.6 mM for 36 days and then at different glucose levels for 19 days. A stock solution with a high glucose concentration (266 mM) was used as the glucose injection solution. The standard error of prediction (SEP) for glucose measurement by the sensor, compared to measurement by the Beckman glucose analyzer, was +/-0.4 mM for 55 days.  相似文献   

18.
A new needle-type sample cell was designed and produced to investigate the correlation between blood glucose and electrical parameters using an impedance analyzer. The characteristics of the measurement cells were optimized to give high sensitivity. High sensitivity complex dielectric constant measurements were obtained by calibration with several known fluids. It was observed that the values of the real (epsilon') and the imaginary (epsilon") dielectric constant increase with decreasing glucose contents in the water/glucose system, and that the value of epsilon' in hamster tail changes according to the variation in blood glucose. It is likely that there is a correlation between blood glucose and the value of epsilon', the electrical parameter.  相似文献   

19.
Two home, blood-glucose monitoring meters, OneTouch Ultra and Ascensia Contour, were used to determine the glucose concentration during fermentations of Trichoderma reesei in both flasks and bioreactors. The results, when compared to those given by the 3,5-dinitrosalicylic acid reducing sugar assay, HPLC and YSI 2700 SELECT Biochemistry analyzer, showed that the glucose meters are a quick, reliable and economical alternative method for frequent glucose concentration measurement during fermentation. For T. reesei fermentations, the OneTouch meter was the more suitable  相似文献   

20.
Sensors for the simultaneous determinations of sucrose and glucose, lactose and glucose, and starch and glucose were prepared by a combination of the enzyme system shown below and an oxygen electrode: The mechanism for separating the substrates with the proposed sensors is based on the time lag arising from reaction and diffusion. Invertase, beta-galactosidase, amyloglucosidase, mutarotase, and glucose oxidase were covalently immobilized on triacetyl cellulose membranes containing 1,8-diamino-4-aminomethyloctane. A glucose oxidase membrane, mutarotase membrane, three sheets of triacetyl cellulose membranes, and invertase, or beta-galactosidase or amyloglucosidase membrane were placed in that order on the tip of the oxygen electrode. Calibration curves for sucrose, lactose, and starch were linear up to 40 mM, 60-180 mM, and 10%, respectively. The simultaneous determination of sucrose and glucose, lactose and glucose, and starch and glucose was possible when the amount of glucose coexised was in the range of 2-16% sucrose, 2.8-8.3% lactose, or 0.1-1% starch. The relative errors were +/-4% for sucrose and +/-3% for lactose in 100 assays. The starch sensor was reused only five times. Each enzyme membrane was fairly stable for more than 10 days.  相似文献   

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