The spatial distribution and population dynamics of Quercus liaotungensis Koidz., Fraxinus rhynchophylla Hance and Acer mono Maxim. were studied in three warm temperate deciduous forests in Dongling Mountain, Beijing....The spatial distribution and population dynamics of Quercus liaotungensis Koidz., Fraxinus rhynchophylla Hance and Acer mono Maxim. were studied in three warm temperate deciduous forests in Dongling Mountain, Beijing. Clumped distributions appeared in most seedlings (≤0.4 m), short saplings (0.4-1 m) and tall saplings (1-2 m). Random distributions appeared in adults of Q. liaotungensis in Plot 1, F. rhynchophylla in Plot 3. The LSD method was used to discern the differences of different aged population. The class distribution of Q. liaotungensis was nearly a reverse-J shape for Plot 1 and Plot 3, suggesting that the population regenerates continuously. The age-structures of F. rhynchophylla and A. mono in Plot 1 and the test results indicated that they would increase continuously. In Plot 2, the class distribution and the test results showed that all populations would not regenerate continuously.展开更多
With in vitro spin labeling electron spin resonance (ESR) spectroscopy, we have studied the effects of Bu Yang Huan Wu (BYHW) decoction and its effective constituents such as astragaloside IV ferulic acid, chua...With in vitro spin labeling electron spin resonance (ESR) spectroscopy, we have studied the effects of Bu Yang Huan Wu (BYHW) decoction and its effective constituents such as astragaloside IV ferulic acid, chuanxiongzine, rutin, chlorogenic acid, 9,10 dimethoxy pterocarpane 7 O β D glucoside, calycosin, formononetin, calycosin 7 O glucoside, paeoniflorin, paeonal and quercein on the cell membrane fluidity of a rat brain which was modeled after the dual cervical arteries were intercepted and released for realizing an ischemia reperfusion injury which was selected as a brain stroke model. Our results indicated that the cell membrane fluidity in the model group decreased approximately 8% compared with the control group, and after brain cells were incubatied with species, the membrane fluidity could be recovered closely to the control level depending on the BYHW decoction and its different constituents. As the membrane fluidity is a very sensitive biological index which reflectsd the cell status, our method will be useful to study the molecular mechanism of tradition Chinese medicine (TCM) and its combination recipe.展开更多
In previous study we reported that pretreatment with plasmolysis enhanced somatic embryo formation in hypocotyls of Eleutherococcus senticosus.In the present study,the expression level of callose synthase gene in embr...In previous study we reported that pretreatment with plasmolysis enhanced somatic embryo formation in hypocotyls of Eleutherococcus senticosus.In the present study,the expression level of callose synthase gene in embryos of E.senticosus in response to 2,4-D,sucrose and mannitol treatments was analyzed by RT-PCR.The results show that plasmolysis pretreatment using sucrose and mannitol significantly promoted the expression of callose synthase gene.Also,the thicker cell walls of explant plasmolyzed compared with controls were observed during the somatic embryogenesis.We suggest that the callose may make the cells in epidermis separate from neighboring cells and then develop into embryogenic potential cells.展开更多
Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the c...Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the content of the active ingredients in product. As to the operation in MAE, the continuous radiation process is more convenient for the extraction for traditional Chinese medicine than the intermittent radiation process. Optimized by uniform design, MAE was proved to be an effective and novel process for extracting active ingredients in Ciwujia. The optimized MAE conditions are as follows: the microwave power is 510W, the radiation time 30min, the alcohol concentration at 80%, the ratio of solvent to solid material being 5:1, the soaking time 0.5h, and the herbal particle size is (520±19)μm.展开更多
[Objective] cDNA of growth hormone releasing hormone （GHRH） receptor gene from Wuzhishan miniature pig was cloned and its sequence was also analyzed. [Method] Using genomic DNA extracted from porcine ear tissues of ...[Objective] cDNA of growth hormone releasing hormone （GHRH） receptor gene from Wuzhishan miniature pig was cloned and its sequence was also analyzed. [Method] Using genomic DNA extracted from porcine ear tissues of Wuzhishan miniature pig as the template, three pairs of primers were designed by the reported cDNA sequence of porcine GHRH, and cDNA was also amplified by RT-PCR. After being recovered and purified, PCR products were ligated to pMD18-T and then transformed into Escherichia coli DH5a. The transformation products were analyzed by PCR and double enzyme digestion to screen positive clones, and the positive clones were sequenced after identification in LB liquid medium. [ Result] cDNA of Wuzhishan miniature pig GHRH receptor gene was obtained successfully, and its length was 1 577 bp coding 423 amino acids. BLAST analysis showed that there were only 23 nuoleotides in difference between this fragment and pomine GHRH receptor gene, and its homology was 98%. However, both GHRH receptor genes were constituted by 423 amino acids with the sequence homology of 96%. [ Conclusion] This study provides theoretical basis for further studies on the dwarf mechanism of Wuzhishan miniature pig.展开更多
This work deals with analysis of dynamic behaviour of hydraulic excavator on the basis of developed dynamic-mathematical model.The mathematical model with maximum five degrees of freedom is extended by new generalized...This work deals with analysis of dynamic behaviour of hydraulic excavator on the basis of developed dynamic-mathematical model.The mathematical model with maximum five degrees of freedom is extended by new generalized coordinate which represents rotation around transversal main central axis of inertia of undercarriage.The excavator is described by a system of six nonlinear,nonhomogenous differential equations of the second kind.Numerical analysis of the differential equations has been done for BTH-600 hydraulic excavator with moving mechanism with pneumatic wheels.展开更多
Random Amplified Polymorphic DNA (RAPD) analysis is a new technology of molecular marking which has proved very powerful in detecting genetic diversity at the level of population. The genomic DNAs used in our experime...Random Amplified Polymorphic DNA (RAPD) analysis is a new technology of molecular marking which has proved very powerful in detecting genetic diversity at the level of population. The genomic DNAs used in our experiment were extracted from fresh leaves taken from 59 individuals sampled from three natural populations in Yan An, Shanxi Province. Through more than 2,000 PCRs, deep-going RAPD analysis was carried out on DNA samples from 49 inviduals. The percentage of polymorphic RAPD loci found in these three populations were respectively 27.2 %, 18.6 % and 5.4 %; the average genetic distances within population, 0.055, 0.036 and 0.008; the average genetic distances between populations (Ⅰ-Ⅱ), (Ⅰ-Ⅲ) and (Ⅱ-Ⅲ), 0.105, 0.096 and 0.060. The genetic diversity of A. brachypus within and between populations was found, for the first time, to be rather poor,thus revealing innate factors as the cause contributing to its endangered status. In addition, our work also provides basic materials for elucidating the underlying cause of its endangerment and for its protection biology.展开更多
The instantaneous speed of a hydraulic system contains a wealth of operational information,and its accurate extraction is the basis for condition monitoring and fault diagnosis.In order to solve the problem of high ha...The instantaneous speed of a hydraulic system contains a wealth of operational information,and its accurate extraction is the basis for condition monitoring and fault diagnosis.In order to solve the problem of high hardware requirement for instantaneous speed measurement based on data acquisition card,a new method of high precision measurement is proposed.In this method,the time-displacement information of each tooth is obtained from the pulsed square wave signal of the gear disk collected by magnetoelectric sensors.The time-displacement curve is interpolated by the cubic spline interpolation method,and then the instantaneous speed is calculated by the five-point digital differential formula.The experimental results show that the method improves the speed measurement resolution and reduces the quantization error.The high precision instantaneous speed signal can also be acquired by hardware devices with less teeth and low sampling frequency.The related research results provide a theoretical basis and a method for improving the accuracy of instantaneous speed measurement.展开更多
In this work,the tunable introduction of oxygen vacancies in bismuth tungstate was realized via asimple solvothermal method with the assistance of iodine doping.With the predictions afforded bytheoretical calculations...In this work,the tunable introduction of oxygen vacancies in bismuth tungstate was realized via asimple solvothermal method with the assistance of iodine doping.With the predictions afforded bytheoretical calculations,the as-prepared bismuth tungstate was characterized using various tech-niques,such as X-ray diffraction,Raman spectroscopy,scanning electron microscopy,transmissionelectron microscopy,X-ray photoelectron spectroscopy,electron spin resonance spectroscopy,anduV-Vis diffuse reflectance spectroscopy.The different concentrations of the oxygen vacancies onbismuth tungstate were found to be intensely correlated with iodine doping,which weakened thelattice oxygen bonds.Owing to the sufficient oxygen vacancies introduced in bismuth tungstate as aresult of iodine doping,the molecular oxygen activation was remarkably enhanced,thus endowingbismuth tungstate with high activity for the photocatalytic degradation of sodium pentachloro-phenate.More encouraging is the total organic carbon removal rate of sodium pentachlorophenateover iodine-doped bismuth tungstate that exceeded 90%in only 2 h and was 10.6 times higher thanthat of the pristine bismuth tungstate under visible light irradiation.Moreover,the mechanism,through which the degradation of sodium pentachlorophenate over iodine-doped bismuth tung-state is enhanced,was speculated based on the results of radical detection and capture experiments.This work provides a new perspective for the enhanced photocatalytic degradation of organochlo-rine pesticides from the oxygen vacancy-induced molecular oxygen activation over iodine-dopedbismuth tungstate.展开更多
Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained fr...Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained from the computer modeling group(CMG) given the reservoir conditions of the Panzhuang block in the southern part of the Qinshui Basin.This is a demonstration region for CBM development located in Shanxi province of northern China.The sensitivity of gas production from a single vertical well to the primary reservoir parameters was estimated first.Then multi-well gas production from three different well patterns was simulated to estimate the most appropriate well spacing.Combining the investment requirements then gave investment-profit efficiencies for these well patterns.A data envelopment analysis(DEA) model was used to optimize the efficiency.The results show that the permeability,the reservoir pressure,and the gas content have an evident impact on single well gas production.The desorption time has little or no affect on production.The equilateral triangular well pattern(ETWP) in a 400 m well spacing is,for multi-well development,the optimal pattern.It has a better input-output ratio,a longer stable yield time,and provides for greater CBM recovery than does either the rectangular well pattern(RWP) or the five point well pattern(FPWP).展开更多
Coupled with partial least squares(PLS),near infrared(NIR)spectroscopy was applied to develop a fast and nondestructive method to identify the production date of Rizhao green tea aiming at the deficiencies of the exis...Coupled with partial least squares(PLS),near infrared(NIR)spectroscopy was applied to develop a fast and nondestructive method to identify the production date of Rizhao green tea aiming at the deficiencies of the existing methods.In the modeling process,the raw spectra were first processed by five-point smoothing and first derivative.And then,moving window back propagation artificial neural network(MW-BP-ANN)was applied to select the characteristic spectral variables.After that,the calibration model was built by PLS,and the optimum model was achieved when 9 principal component scores(PCs)were included.The performances of the calibration models were evaluated according to root mean square error of predictionεRMSEP,correlation coefficient(C p)and residual prediction deviation(σRPD).The optimum results of the calibration model was achieved,andεRMSEP=19.965,C p=0.943 andσRPD=3.07.The overall results sufficiently demonstrate that NIR spectroscopy combined with PLS can be efficiently applied in the rapid identification of green tea production date.展开更多
AIM： Gastric inhibitory polypeptide is secreted from intestinal K-cells in response to nutrient ingestion and acts as an incretin hormone in human physiology. While animal experiments suggested a role for GIP as an i...AIM： Gastric inhibitory polypeptide is secreted from intestinal K-cells in response to nutrient ingestion and acts as an incretin hormone in human physiology. While animal experiments suggested a role for GIP as an inhibitor of gastric secretion, the GIP effects on gastric acid output in humans are still controversial. METHODS： Pentagastrin was administered at an infusion rate of 1 μg . kg^-1 . h^-1 over 300 min in 8 patients with type 2 diabetes （2 female, 6 male, 54± 10 years, BMI 30.5 ± 2.2 kg/m^2; no history of autonomic neuropathy） and 8 healthy subjects （2/6, 46 ± 6 years., 28.9 ± 5.3 kg/ m^2）. A hyperglycaemic clamp （140 mg/dl） was performed over 240 min. Placebo, GIP at a physiological dose （1 pmol . kg^-1 . min^-1）, and GIP at a pharmacological dose （4 mol . kg^-1 . min^-1） were administered over 60 min each. Boluses of placebo, 20 pmol GIP/kg, and 80 pmol GIP/kg were injected intravenously at the beginning of each infusion period, respectively. Gastric volume, acid and chloride output were analysed in 15-min intervals. Capillary and venous blood samples were drawn for the determination of glucose and total GIP. Statistics were carried out by repeated-measures ANOVA and one-way ANOVA. RESULTS： Plasma glucose concentrations during the hyperglycaemic clamp experiments were not different between patients with type 2 diabetes and controls. Steady-state GIP plasma levels were 61 ±8 and 79 ± 12 pmol/I during the low-dose and 327±35 and 327± 17 pmol/I during the high-dose infusion of GIP, in healthy control subjects and in patients with type 2 diabetes, respectively （P= 0.23 and p 0.99）. Pentagastrin markedly increased gastric acid and chloride secretion （P〈 0.001）. There were no significant differences in the rates of gastric acid or chloride output between the experimental periods with placebo or any dose of GIP. The temporal patterns of gastric acid and chloride secretion were similar in patients with type 2 diabetes and healthy controls （P= 0.86 and P= 0.61, respectively）. CONCLUSION： Pentagastrin-stimulated gastric acid secretion is similar in patients with type 2 diabetes and healthy controls. GIP administration does not influence gastric acid secretion at physiological or pharmacological plasma levels. Therefore, GIP appears to act as an incretin rather than as an enterogastrone in human physiology.展开更多
A new process is proposed for refining niobite ore that is found in Jiangxi province of China. Niobite, also known as columbite or niobite-tantalite, is a mineral that contains tantalum and niobium. The separation pro...A new process is proposed for refining niobite ore that is found in Jiangxi province of China. Niobite, also known as columbite or niobite-tantalite, is a mineral that contains tantalum and niobium. The separation process includes two-stage grinding, gravity concentration, magnetic separation, and flotation. The tan- talum/niobium concentrate obtained had a grade of Ta2O5 18.28%, Nb2O5 41.62% at a recovery rate of Ta2O5 49.08%, Nb205 70.77%. Other minerals occurring along with the niobite, such as zinnwaldite, feld- spar, and quartz, were also recovered to comprehensively utilize this ore.展开更多
Tolerance of a facultative marine fungus Aspergillus flavus towards As (V) was tested.Luxuriant growth of the test isolate was observed in culture media with As (V) concentrations of 25 mg L-1 and 50 mg L-1,indicating...Tolerance of a facultative marine fungus Aspergillus flavus towards As (V) was tested.Luxuriant growth of the test isolate was observed in culture media with As (V) concentrations of 25 mg L-1 and 50 mg L-1,indicating its tolerance to the metal.Accumulation rate of arsenic was always higher when exposed to As (V) at 50 mg L-1 than at 25 mg L-1.The study reveals Aspergillus flavus as a promising candidate for environmental bioremediation.Arsenic contents (mg g-1) in the fungus when exposed to 50 mg L-1 As (V) were measured as 11.1773,4.0983,and 8.0000 mg g-1 on day 3,6 and 9,respectively.The highest content was observed initially,i.e.on day 3,followed by a decline and a rise again.These results provide baseline information for further explorations regarding the exploitation of the fungus for arsenic removal.展开更多
文摘The spatial distribution and population dynamics of Quercus liaotungensis Koidz., Fraxinus rhynchophylla Hance and Acer mono Maxim. were studied in three warm temperate deciduous forests in Dongling Mountain, Beijing. Clumped distributions appeared in most seedlings (≤0.4 m), short saplings (0.4-1 m) and tall saplings (1-2 m). Random distributions appeared in adults of Q. liaotungensis in Plot 1, F. rhynchophylla in Plot 3. The LSD method was used to discern the differences of different aged population. The class distribution of Q. liaotungensis was nearly a reverse-J shape for Plot 1 and Plot 3, suggesting that the population regenerates continuously. The age-structures of F. rhynchophylla and A. mono in Plot 1 and the test results indicated that they would increase continuously. In Plot 2, the class distribution and the test results showed that all populations would not regenerate continuously.
文摘With in vitro spin labeling electron spin resonance (ESR) spectroscopy, we have studied the effects of Bu Yang Huan Wu (BYHW) decoction and its effective constituents such as astragaloside IV ferulic acid, chuanxiongzine, rutin, chlorogenic acid, 9,10 dimethoxy pterocarpane 7 O β D glucoside, calycosin, formononetin, calycosin 7 O glucoside, paeoniflorin, paeonal and quercein on the cell membrane fluidity of a rat brain which was modeled after the dual cervical arteries were intercepted and released for realizing an ischemia reperfusion injury which was selected as a brain stroke model. Our results indicated that the cell membrane fluidity in the model group decreased approximately 8% compared with the control group, and after brain cells were incubatied with species, the membrane fluidity could be recovered closely to the control level depending on the BYHW decoction and its different constituents. As the membrane fluidity is a very sensitive biological index which reflectsd the cell status, our method will be useful to study the molecular mechanism of tradition Chinese medicine (TCM) and its combination recipe.
基金supported by the 948 Program of State Forestry Administration (No2009-4-26)co-sponsored by SRF for ROCS and the National Natural Science Foundation (No 30972390) of China
文摘In previous study we reported that pretreatment with plasmolysis enhanced somatic embryo formation in hypocotyls of Eleutherococcus senticosus.In the present study,the expression level of callose synthase gene in embryos of E.senticosus in response to 2,4-D,sucrose and mannitol treatments was analyzed by RT-PCR.The results show that plasmolysis pretreatment using sucrose and mannitol significantly promoted the expression of callose synthase gene.Also,the thicker cell walls of explant plasmolyzed compared with controls were observed during the somatic embryogenesis.We suggest that the callose may make the cells in epidermis separate from neighboring cells and then develop into embryogenic potential cells.
文摘Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the content of the active ingredients in product. As to the operation in MAE, the continuous radiation process is more convenient for the extraction for traditional Chinese medicine than the intermittent radiation process. Optimized by uniform design, MAE was proved to be an effective and novel process for extracting active ingredients in Ciwujia. The optimized MAE conditions are as follows: the microwave power is 510W, the radiation time 30min, the alcohol concentration at 80%, the ratio of solvent to solid material being 5:1, the soaking time 0.5h, and the herbal particle size is (520±19)μm.
基金Supported by Natural Science Foundation of Hainan Province(30515)~~
文摘[Objective] cDNA of growth hormone releasing hormone （GHRH） receptor gene from Wuzhishan miniature pig was cloned and its sequence was also analyzed. [Method] Using genomic DNA extracted from porcine ear tissues of Wuzhishan miniature pig as the template, three pairs of primers were designed by the reported cDNA sequence of porcine GHRH, and cDNA was also amplified by RT-PCR. After being recovered and purified, PCR products were ligated to pMD18-T and then transformed into Escherichia coli DH5a. The transformation products were analyzed by PCR and double enzyme digestion to screen positive clones, and the positive clones were sequenced after identification in LB liquid medium. [ Result] cDNA of Wuzhishan miniature pig GHRH receptor gene was obtained successfully, and its length was 1 577 bp coding 423 amino acids. BLAST analysis showed that there were only 23 nuoleotides in difference between this fragment and pomine GHRH receptor gene, and its homology was 98%. However, both GHRH receptor genes were constituted by 423 amino acids with the sequence homology of 96%. [ Conclusion] This study provides theoretical basis for further studies on the dwarf mechanism of Wuzhishan miniature pig.
文摘This work deals with analysis of dynamic behaviour of hydraulic excavator on the basis of developed dynamic-mathematical model.The mathematical model with maximum five degrees of freedom is extended by new generalized coordinate which represents rotation around transversal main central axis of inertia of undercarriage.The excavator is described by a system of six nonlinear,nonhomogenous differential equations of the second kind.Numerical analysis of the differential equations has been done for BTH-600 hydraulic excavator with moving mechanism with pneumatic wheels.
文摘Random Amplified Polymorphic DNA (RAPD) analysis is a new technology of molecular marking which has proved very powerful in detecting genetic diversity at the level of population. The genomic DNAs used in our experiment were extracted from fresh leaves taken from 59 individuals sampled from three natural populations in Yan An, Shanxi Province. Through more than 2,000 PCRs, deep-going RAPD analysis was carried out on DNA samples from 49 inviduals. The percentage of polymorphic RAPD loci found in these three populations were respectively 27.2 %, 18.6 % and 5.4 %; the average genetic distances within population, 0.055, 0.036 and 0.008; the average genetic distances between populations (Ⅰ-Ⅱ), (Ⅰ-Ⅲ) and (Ⅱ-Ⅲ), 0.105, 0.096 and 0.060. The genetic diversity of A. brachypus within and between populations was found, for the first time, to be rather poor,thus revealing innate factors as the cause contributing to its endangered status. In addition, our work also provides basic materials for elucidating the underlying cause of its endangerment and for its protection biology.
基金National Natural Science Foundation of China(No.51275375)Scientific Research Program Project of Shaanxi Provincial Education Department(No.19JK0464)
文摘The instantaneous speed of a hydraulic system contains a wealth of operational information,and its accurate extraction is the basis for condition monitoring and fault diagnosis.In order to solve the problem of high hardware requirement for instantaneous speed measurement based on data acquisition card,a new method of high precision measurement is proposed.In this method,the time-displacement information of each tooth is obtained from the pulsed square wave signal of the gear disk collected by magnetoelectric sensors.The time-displacement curve is interpolated by the cubic spline interpolation method,and then the instantaneous speed is calculated by the five-point digital differential formula.The experimental results show that the method improves the speed measurement resolution and reduces the quantization error.The high precision instantaneous speed signal can also be acquired by hardware devices with less teeth and low sampling frequency.The related research results provide a theoretical basis and a method for improving the accuracy of instantaneous speed measurement.
文摘In this work,the tunable introduction of oxygen vacancies in bismuth tungstate was realized via asimple solvothermal method with the assistance of iodine doping.With the predictions afforded bytheoretical calculations,the as-prepared bismuth tungstate was characterized using various tech-niques,such as X-ray diffraction,Raman spectroscopy,scanning electron microscopy,transmissionelectron microscopy,X-ray photoelectron spectroscopy,electron spin resonance spectroscopy,anduV-Vis diffuse reflectance spectroscopy.The different concentrations of the oxygen vacancies onbismuth tungstate were found to be intensely correlated with iodine doping,which weakened thelattice oxygen bonds.Owing to the sufficient oxygen vacancies introduced in bismuth tungstate as aresult of iodine doping,the molecular oxygen activation was remarkably enhanced,thus endowingbismuth tungstate with high activity for the photocatalytic degradation of sodium pentachloro-phenate.More encouraging is the total organic carbon removal rate of sodium pentachlorophenateover iodine-doped bismuth tungstate that exceeded 90%in only 2 h and was 10.6 times higher thanthat of the pristine bismuth tungstate under visible light irradiation.Moreover,the mechanism,through which the degradation of sodium pentachlorophenate over iodine-doped bismuth tung-state is enhanced,was speculated based on the results of radical detection and capture experiments.This work provides a new perspective for the enhanced photocatalytic degradation of organochlo-rine pesticides from the oxygen vacancy-induced molecular oxygen activation over iodine-dopedbismuth tungstate.
基金supported by the National Natural Science Foundation of China (No. 40972207)the National Science and Technology Major Projects (No. 2011ZX05034-005)the PAPD of Jiangsu Higher Education Institutions
文摘Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained from the computer modeling group(CMG) given the reservoir conditions of the Panzhuang block in the southern part of the Qinshui Basin.This is a demonstration region for CBM development located in Shanxi province of northern China.The sensitivity of gas production from a single vertical well to the primary reservoir parameters was estimated first.Then multi-well gas production from three different well patterns was simulated to estimate the most appropriate well spacing.Combining the investment requirements then gave investment-profit efficiencies for these well patterns.A data envelopment analysis(DEA) model was used to optimize the efficiency.The results show that the permeability,the reservoir pressure,and the gas content have an evident impact on single well gas production.The desorption time has little or no affect on production.The equilateral triangular well pattern(ETWP) in a 400 m well spacing is,for multi-well development,the optimal pattern.It has a better input-output ratio,a longer stable yield time,and provides for greater CBM recovery than does either the rectangular well pattern(RWP) or the five point well pattern(FPWP).
基金National Basic Research Program of China(No.JSJL2016210A001)State Key Laboratory of Sensor Technology Fund(No.SKT1507)
文摘Coupled with partial least squares(PLS),near infrared(NIR)spectroscopy was applied to develop a fast and nondestructive method to identify the production date of Rizhao green tea aiming at the deficiencies of the existing methods.In the modeling process,the raw spectra were first processed by five-point smoothing and first derivative.And then,moving window back propagation artificial neural network(MW-BP-ANN)was applied to select the characteristic spectral variables.After that,the calibration model was built by PLS,and the optimum model was achieved when 9 principal component scores(PCs)were included.The performances of the calibration models were evaluated according to root mean square error of predictionεRMSEP,correlation coefficient(C p)and residual prediction deviation(σRPD).The optimum results of the calibration model was achieved,andεRMSEP=19.965,C p=0.943 andσRPD=3.07.The overall results sufficiently demonstrate that NIR spectroscopy combined with PLS can be efficiently applied in the rapid identification of green tea production date.
基金Supported by the Wilhelm-Sander-Stiftung(No.2002.025.1 to JJM)Deutsche Forschungsgemeinschaft(grants Me 2096/2-1,Na 203/6-1 and Ga 386/8-1)the Deutsche Diabetes Gesellschaft(to JJM)
文摘AIM： Gastric inhibitory polypeptide is secreted from intestinal K-cells in response to nutrient ingestion and acts as an incretin hormone in human physiology. While animal experiments suggested a role for GIP as an inhibitor of gastric secretion, the GIP effects on gastric acid output in humans are still controversial. METHODS： Pentagastrin was administered at an infusion rate of 1 μg . kg^-1 . h^-1 over 300 min in 8 patients with type 2 diabetes （2 female, 6 male, 54± 10 years, BMI 30.5 ± 2.2 kg/m^2; no history of autonomic neuropathy） and 8 healthy subjects （2/6, 46 ± 6 years., 28.9 ± 5.3 kg/ m^2）. A hyperglycaemic clamp （140 mg/dl） was performed over 240 min. Placebo, GIP at a physiological dose （1 pmol . kg^-1 . min^-1）, and GIP at a pharmacological dose （4 mol . kg^-1 . min^-1） were administered over 60 min each. Boluses of placebo, 20 pmol GIP/kg, and 80 pmol GIP/kg were injected intravenously at the beginning of each infusion period, respectively. Gastric volume, acid and chloride output were analysed in 15-min intervals. Capillary and venous blood samples were drawn for the determination of glucose and total GIP. Statistics were carried out by repeated-measures ANOVA and one-way ANOVA. RESULTS： Plasma glucose concentrations during the hyperglycaemic clamp experiments were not different between patients with type 2 diabetes and controls. Steady-state GIP plasma levels were 61 ±8 and 79 ± 12 pmol/I during the low-dose and 327±35 and 327± 17 pmol/I during the high-dose infusion of GIP, in healthy control subjects and in patients with type 2 diabetes, respectively （P= 0.23 and p 0.99）. Pentagastrin markedly increased gastric acid and chloride secretion （P〈 0.001）. There were no significant differences in the rates of gastric acid or chloride output between the experimental periods with placebo or any dose of GIP. The temporal patterns of gastric acid and chloride secretion were similar in patients with type 2 diabetes and healthy controls （P= 0.86 and P= 0.61, respectively）. CONCLUSION： Pentagastrin-stimulated gastric acid secretion is similar in patients with type 2 diabetes and healthy controls. GIP administration does not influence gastric acid secretion at physiological or pharmacological plasma levels. Therefore, GIP appears to act as an incretin rather than as an enterogastrone in human physiology.
基金the Geological Survey Program fromthe Ministry of Land and Resources of China (No. 1212010816036)and the National Department Public Benefit Research Foundation from Ministry of Land and Resources of China (No. 201011031)Zhengzhou Institute of Multipurpose Utilization of Mineral Resources CAGS,for financial support and approval of this paper for publication
文摘A new process is proposed for refining niobite ore that is found in Jiangxi province of China. Niobite, also known as columbite or niobite-tantalite, is a mineral that contains tantalum and niobium. The separation process includes two-stage grinding, gravity concentration, magnetic separation, and flotation. The tan- talum/niobium concentrate obtained had a grade of Ta2O5 18.28%, Nb2O5 41.62% at a recovery rate of Ta2O5 49.08%, Nb205 70.77%. Other minerals occurring along with the niobite, such as zinnwaldite, feld- spar, and quartz, were also recovered to comprehensively utilize this ore.
基金due to the Department of Science and Technology,Government of India,for financial support sanctioned under SERC Fast Track Proposals for Young Scientists Scheme (No. SR/FT/L-99/2006) to AKV
文摘Tolerance of a facultative marine fungus Aspergillus flavus towards As (V) was tested.Luxuriant growth of the test isolate was observed in culture media with As (V) concentrations of 25 mg L-1 and 50 mg L-1,indicating its tolerance to the metal.Accumulation rate of arsenic was always higher when exposed to As (V) at 50 mg L-1 than at 25 mg L-1.The study reveals Aspergillus flavus as a promising candidate for environmental bioremediation.Arsenic contents (mg g-1) in the fungus when exposed to 50 mg L-1 As (V) were measured as 11.1773,4.0983,and 8.0000 mg g-1 on day 3,6 and 9,respectively.The highest content was observed initially,i.e.on day 3,followed by a decline and a rise again.These results provide baseline information for further explorations regarding the exploitation of the fungus for arsenic removal.
