As the demands of massive connections and vast coverage rapidly grow in the next wireless communication networks, rate splitting multiple access(RSMA) is considered to be the new promising access scheme since it can p...As the demands of massive connections and vast coverage rapidly grow in the next wireless communication networks, rate splitting multiple access(RSMA) is considered to be the new promising access scheme since it can provide higher efficiency with limited spectrum resources. In this paper, combining spectrum splitting with rate splitting, we propose to allocate resources with traffic offloading in hybrid satellite terrestrial networks. A novel deep reinforcement learning method is adopted to solve this challenging non-convex problem. However, the neverending learning process could prohibit its practical implementation. Therefore, we introduce the switch mechanism to avoid unnecessary learning. Additionally, the QoS constraint in the scheme can rule out unsuccessful transmission. The simulation results validates the energy efficiency performance and the convergence speed of the proposed algorithm.展开更多
During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by...During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by controllable (operation pressure, gasification time, geometry of UCG panel) and uncontrollable (coal seam properties) factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR.展开更多
Rate splitting multiple access(RSMA)has shown great potentials for the next generation communication systems.In this work,we consider a two-user system in hybrid satellite terrestrial network(HSTN)where one of them is...Rate splitting multiple access(RSMA)has shown great potentials for the next generation communication systems.In this work,we consider a two-user system in hybrid satellite terrestrial network(HSTN)where one of them is heavily shadowed and the other uses cooperative RSMA to improve the transmission quality.The non-convex weighted sum rate(WSR)problem formulated based on this model is usually optimized by computational burdened weighted minimum mean square error(WMMSE)algorithm.We propose to apply deep unfolding to solve the optimization problem,which maps WMMSE iterations into a layer-wise network and could achieve better performance within limited iterations.We also incorporate momentum accelerated projection gradient descent(PGD)algorithm to circumvent the complicated operations in WMMSE that are not amenable for unfolding and mapping.The momentum and step size in deep unfolding network are selected as trainable parameters for training.As shown in the simulation results,deep unfolding scheme has WSR and convergence speed advantages over original WMMSE algorithm.展开更多
A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation e...A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation energyE; the pre-exponential factorA is obtained on the basis ofE andg(α). By this new method, the thermal analysis kinetics triplet of dehydration of cobalt oxalate dihydrate is determined, apparent activation energyE is 99.84 kJ·mol?1; pre-exponential factorA is 3.427×109–3.872×109 s?1 and the most probable mechanism belongs to nucleation and growth,A m model, the range ofm is from 1.50 to 1.70. Key words multiple rates isotemperature method - isoconversional method - cobalt oxalate dihydrate - accomodation function - differential scanning calorimetry (DSC) CLC number O 636.1 Foundation item: Supported by the Key Foundation of the Science and Technology Committee of Hubei Province (2001ABA009)Biography: Li Li-qing (1977-), female, Master candidate, research direction: material synthesize and thermal analysis kinetics.展开更多
Background The emergence of pink bollworm(PBW),Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae),in cotton due to Bt resistance and concealed feeding habit has created a need for alternative,eco-friendly,and...Background The emergence of pink bollworm(PBW),Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae),in cotton due to Bt resistance and concealed feeding habit has created a need for alternative,eco-friendly,and cost-effective control methods.This study aimed to evaluate the bio-efficacy and reproductive potential of two native strains of entomopathogenic nematodes(EPNs),Heterorhabditis indica,namely CICR-HI-CL and CICR-HI-MN,against PBW larvae and pupae under in-vitro conditions.Results The larval assay revealed that strain CICR-HI-CL exhibited higher potency than strain CICR-HI-MN against 2nd,3rd,and 4thinstar larvae,with median lethal dose(LD50)values of 5.45,4.45,and 4.60 infective juveniles(IJs)per larva,respectively.In case of pupal bioassay,both EPN strains demonstrated greater virulence when applied directly(LD50values:29.65 and 73.88 IJs per pupa for strains CICR-HI-CL and CICR-HI-MN,respectively)compared to soil application(147.84 and 272.38 IJs per pupa).Both EPN strains successfully penetrated and reproduced on 4thinstar larvae,resulting in maximum production of 19.28 and 20.85 lakh IJs per larva in the next generation when inoculated at 30 IJs per larva.Conclusion The present study has generated useful information on the virulence and reproductive potential of two strains of EPN H.indica(CICR-HI-CL and CICR-HI-MN)against PBW,a dreaded pest of cotton.Higher virulence and reproductive potential of EPN strains demonstrated their ability to multiply,sustain and perpetuate on larval and pupal stages of PBW.The knowledge generated will help formulate effective management strategies for PBW with the inclusion of EPN as a potential biological control candidate.The soil-dwelling life stages viz.,last instar hibernating larvae and pupae of PBW can be the ideal weak links to make a successful use of H.indica for sustainable management of PBW in the cotton ecosystem.However,before taking these EPN strains to field for managing PBW,detailed studies investigating their biocontrol potential against PBW under field conditions are needed.展开更多
Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia (Maiden & Betche) Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propaga...Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia (Maiden & Betche) Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 + BA 0.6mg L^-1 +NAA 0.1 mg L^-1+sucrose 30g L-l, which yielded a 75.9 % initiation rate. An efficient multi- plication medium was MS + BA 0.3 mg L^-1+ NAA 0.15 mg L^-1 + sucrose 30 g L^-1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 + IBA 0.1-0.25 mg L^-1 + sucrose 15 g L^-1, which yielded a 100 % rooting rate, 2.94-3.32 roots per individual and 1.36-1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.展开更多
The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results...The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results show that the extent and duration of the inhibitory effect on the metabolism as judged from the multiplication rate constant, k , varies with different Schiff bases. The multiplication rate constant k , of Escherichia coli (in log phase) in the presence of Mo salicylioaldehyde thiadizole, Mo piperonaldehyde thiosemicarbazone and Mo 3 methoxy salicylicaldehyde thiadizole decreases with the increase of concentrations of compounds c , and the relationships between k and c , maximum heat production rate p m and c , peak time of growth curves t p and c are of linearity. For Mo 6 nitro pieronalde thiosemicarbazone, the multiplication rate constant is constant irrespective of variation in concentration. The sequence of antibiotic activity of Schiff base is : Mo salicylioaldehyde thiadizole>Mo 3 methoxy salicylicaldehyde thiadizole>Mo piperonaldehyde thiosemicarbazone>6 nitro pieronalde thiosemicarbazone.展开更多
In a completely randomized blocks (RCB) plot, we planted seed from the three segments of Kponan tubers: head, median and tail portions with control Krengle. Germination began 10 d and lasted 67 d. The mean sproutin...In a completely randomized blocks (RCB) plot, we planted seed from the three segments of Kponan tubers: head, median and tail portions with control Krengle. Germination began 10 d and lasted 67 d. The mean sprouting rate of the Kponan full season harvest tuber was 78.1% compared to 94% in Krengle. However, the tuber germination was progressive from head to tail with a linear evolution of the top fragments with sprouting rate up to 90% similar to Krengle. The median and distal portions sprout two and three weeks later with final raising rates reaching 68% and 71%, respectively. The full season tuber of Kponan sprouts with a good rate gave good yields for any portion of the tuber. It had a sprouting gradient oriented from the proximal portion to the distal one, while yield was better for medium seeds. The sprouting delays two weeks between proximal and medium portions and three weeks between proximal and distal portions were acceptable with regards to the total cycle of eight to nine months period. Thus, its small tubers could be planted as well as the top portion of big tuber. In terms of yield, Kponan medium seed gave the best yield 34.25 t/ha and the whole Kponan tuber yield was more than Krengle. That led to a better multiplication factor for Kponan full season tuber. The type of tuber, if available, could be used as seed for yam production. That could improve its distribution and contribute to food security.展开更多
We investigated a series of novel motors and pumps with a new structure called double-stator. Double-stator can be used as pump or motor just for the working condition on demand. A certain amount of pumps or motors ar...We investigated a series of novel motors and pumps with a new structure called double-stator. Double-stator can be used as pump or motor just for the working condition on demand. A certain amount of pumps or motors are formed in one shell and these subpumps or submotors can work alone or in company without influence on other pumps or moters. This kind of double-stator pumps (motors) are called multi-pumps (multi-motors). Through the analysis of multifarious connection modes of single-acting double-stator multi-pumps and multi-motors, the mathematical expressions of output flow rate, rotational speed and torque are acquired. The results indicate that different flow rates can be provided by one fixed displacement double-stator multi-pump system under the condition of an unalterable driven speed. Likewise, under the terms of a fixed input flow and without complex variable mechanisms, the functions of double speeds, multiple speeds and even differential connection can be realized by a double-stator multi-motor system with various output rotational speeds and torques.展开更多
Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reac...Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and kerogens.The characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A trend.Important similarities and differences are observed between the TF profile values of the two datasets.The similarities support the spread of E-A values involved in shale pyrogram best fits.The differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions simulated.The results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A values.In contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale formations.TF profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.展开更多
Nitrous oxide(N_2O) is a potent greenhouse gas that can be emitted during biological nitrogen removal. N_2O emission was examined in a multiple anoxic and aerobic process at the aeration rates of 600 m L/min sequenc...Nitrous oxide(N_2O) is a potent greenhouse gas that can be emitted during biological nitrogen removal. N_2O emission was examined in a multiple anoxic and aerobic process at the aeration rates of 600 m L/min sequencing batch reactor(SBRL) and 1200 m L/min(SBRH).The nitrogen removal percentage was 89% in SBRLand 71% in SBRH, respectively. N_2O emission mainly occurred during the aerobic phase, and the N_2O emission factor was 10.1%in SBRLand 2.3% in SBRH, respectively. In all batch experiments, the N_2O emission potential was high in SBRLcompared with SBRH. In SBRL, with increasing aeration rates, the N_2O emission factor decreased during nitrification, while it increased during denitrification and simultaneous nitrification and denitrification(SND). By contrast, in SBRHthe N_2O emission factor during nitrification, denitrification and SND was relatively low and changed little with increasing aeration rates. The microbial competition affected the N_2O emission during biological nitrogen removal.展开更多
Subject Code:D05Under support of the National Natural Science Foundation of China,a concerted study by Dr.Huang Gang(黄刚)from the Institute of Atmospheric Physics,Chinese Academy of Sciences,climate scientist Jing-Ji...Subject Code:D05Under support of the National Natural Science Foundation of China,a concerted study by Dr.Huang Gang(黄刚)from the Institute of Atmospheric Physics,Chinese Academy of Sciences,climate scientist Jing-Jia Luo from the Australian Bureau of Meteorology,Dr.Yao Shuailei(姚帅磊)from the Institute展开更多
Objective To study the effect of patient age, the number and quality of embryos transferred on pregnancy outcome in in vitro fertilization-embryo transfer procedures (IVF-ETs). Methods A retrospective study was cond...Objective To study the effect of patient age, the number and quality of embryos transferred on pregnancy outcome in in vitro fertilization-embryo transfer procedures (IVF-ETs). Methods A retrospective study was conducted with infertile women who underwent a total of 1 800 cycles of lVF-ET and intracytoplasmic sperm injection (ICSI) at the Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical College from Jan. 2006 to Dec. 2007. The patients were divided into three groups based on age (year). 〈30, 30-34 and 235. The rates of clinical pregnancy and multiple pregnancies were compared in each group when 1-3 embryos and 0-3 goodquality embryos were transferred respectively. Results 1) In the group of patients aged 〈30 years, there was no significant difference in pregnancy outcomes with 1-3 embryos transferred. However, pregnancy rates were similar when 2 3 good-quality embryos were transferred, which was significantly higher compared with 0-1 good-quality embryos transferred; the incidence of multiple pregnancies was not an issue when only 1 embryo was transferred. 2) The pregnancy rate of the patients aged 30 34 was not significant not only when only 2-3 embryos were transferred but also when 2-3 good-quality embryos were transferred, which was significant compared with when 1 embryo or 0 1 good-quality embryo was transferred. The subgroup of 3 good-quality embryos transferred, at the same time, was expected to significantly increase multiple pregnancy rate. 3) For the patients aged 235, there were similar pregnancy rates in the subgroup involving 1-3 embryos transferred. Compared with 0-2 good-quality embryos transferred, the pregnancy rate was significantly higher in the patients with 3 good-quality embryos transferred. An increased trend toward multiple pregnancies was observed among not only the subgroups with 1-3 embryos transferred, but also when 1-3 good-quality embryos were transferred, although it was significantly higher in patients with 3 good-quality embryo transferred. Conclusion In an effort to achieve the ideal pregnancy rate without the risk of multiple pregnancies, it is desirable to employ a single good-quality embryo transfer for patients aged 〈30 years and 2 good-quality embryos for patients aged 330. As older women (aged 335 years), this is important, need to abstain from poor-quality embryo transferred by increasing the number of embryos transferred in an effort to improve the rate of clinical pregnancy, if the patients have had enough 2 high-quality embryos.展开更多
文摘As the demands of massive connections and vast coverage rapidly grow in the next wireless communication networks, rate splitting multiple access(RSMA) is considered to be the new promising access scheme since it can provide higher efficiency with limited spectrum resources. In this paper, combining spectrum splitting with rate splitting, we propose to allocate resources with traffic offloading in hybrid satellite terrestrial networks. A novel deep reinforcement learning method is adopted to solve this challenging non-convex problem. However, the neverending learning process could prohibit its practical implementation. Therefore, we introduce the switch mechanism to avoid unnecessary learning. Additionally, the QoS constraint in the scheme can rule out unsuccessful transmission. The simulation results validates the energy efficiency performance and the convergence speed of the proposed algorithm.
文摘During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by controllable (operation pressure, gasification time, geometry of UCG panel) and uncontrollable (coal seam properties) factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR.
基金sponsored by National Natural Science Foundation of China (No. 61871422, No.62027801)
文摘Rate splitting multiple access(RSMA)has shown great potentials for the next generation communication systems.In this work,we consider a two-user system in hybrid satellite terrestrial network(HSTN)where one of them is heavily shadowed and the other uses cooperative RSMA to improve the transmission quality.The non-convex weighted sum rate(WSR)problem formulated based on this model is usually optimized by computational burdened weighted minimum mean square error(WMMSE)algorithm.We propose to apply deep unfolding to solve the optimization problem,which maps WMMSE iterations into a layer-wise network and could achieve better performance within limited iterations.We also incorporate momentum accelerated projection gradient descent(PGD)algorithm to circumvent the complicated operations in WMMSE that are not amenable for unfolding and mapping.The momentum and step size in deep unfolding network are selected as trainable parameters for training.As shown in the simulation results,deep unfolding scheme has WSR and convergence speed advantages over original WMMSE algorithm.
文摘A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation energyE; the pre-exponential factorA is obtained on the basis ofE andg(α). By this new method, the thermal analysis kinetics triplet of dehydration of cobalt oxalate dihydrate is determined, apparent activation energyE is 99.84 kJ·mol?1; pre-exponential factorA is 3.427×109–3.872×109 s?1 and the most probable mechanism belongs to nucleation and growth,A m model, the range ofm is from 1.50 to 1.70. Key words multiple rates isotemperature method - isoconversional method - cobalt oxalate dihydrate - accomodation function - differential scanning calorimetry (DSC) CLC number O 636.1 Foundation item: Supported by the Key Foundation of the Science and Technology Committee of Hubei Province (2001ABA009)Biography: Li Li-qing (1977-), female, Master candidate, research direction: material synthesize and thermal analysis kinetics.
基金the Indian Council of Agricultural Research,New Delhi for the grant in aid through ICAR-Central Institute for Cotton Research,Nagpur Institutional Project。
文摘Background The emergence of pink bollworm(PBW),Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae),in cotton due to Bt resistance and concealed feeding habit has created a need for alternative,eco-friendly,and cost-effective control methods.This study aimed to evaluate the bio-efficacy and reproductive potential of two native strains of entomopathogenic nematodes(EPNs),Heterorhabditis indica,namely CICR-HI-CL and CICR-HI-MN,against PBW larvae and pupae under in-vitro conditions.Results The larval assay revealed that strain CICR-HI-CL exhibited higher potency than strain CICR-HI-MN against 2nd,3rd,and 4thinstar larvae,with median lethal dose(LD50)values of 5.45,4.45,and 4.60 infective juveniles(IJs)per larva,respectively.In case of pupal bioassay,both EPN strains demonstrated greater virulence when applied directly(LD50values:29.65 and 73.88 IJs per pupa for strains CICR-HI-CL and CICR-HI-MN,respectively)compared to soil application(147.84 and 272.38 IJs per pupa).Both EPN strains successfully penetrated and reproduced on 4thinstar larvae,resulting in maximum production of 19.28 and 20.85 lakh IJs per larva in the next generation when inoculated at 30 IJs per larva.Conclusion The present study has generated useful information on the virulence and reproductive potential of two strains of EPN H.indica(CICR-HI-CL and CICR-HI-MN)against PBW,a dreaded pest of cotton.Higher virulence and reproductive potential of EPN strains demonstrated their ability to multiply,sustain and perpetuate on larval and pupal stages of PBW.The knowledge generated will help formulate effective management strategies for PBW with the inclusion of EPN as a potential biological control candidate.The soil-dwelling life stages viz.,last instar hibernating larvae and pupae of PBW can be the ideal weak links to make a successful use of H.indica for sustainable management of PBW in the cotton ecosystem.However,before taking these EPN strains to field for managing PBW,detailed studies investigating their biocontrol potential against PBW under field conditions are needed.
文摘Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia (Maiden & Betche) Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 + BA 0.6mg L^-1 +NAA 0.1 mg L^-1+sucrose 30g L-l, which yielded a 75.9 % initiation rate. An efficient multi- plication medium was MS + BA 0.3 mg L^-1+ NAA 0.15 mg L^-1 + sucrose 30 g L^-1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 + IBA 0.1-0.25 mg L^-1 + sucrose 15 g L^-1, which yielded a 100 % rooting rate, 2.94-3.32 roots per individual and 1.36-1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.
文摘The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results show that the extent and duration of the inhibitory effect on the metabolism as judged from the multiplication rate constant, k , varies with different Schiff bases. The multiplication rate constant k , of Escherichia coli (in log phase) in the presence of Mo salicylioaldehyde thiadizole, Mo piperonaldehyde thiosemicarbazone and Mo 3 methoxy salicylicaldehyde thiadizole decreases with the increase of concentrations of compounds c , and the relationships between k and c , maximum heat production rate p m and c , peak time of growth curves t p and c are of linearity. For Mo 6 nitro pieronalde thiosemicarbazone, the multiplication rate constant is constant irrespective of variation in concentration. The sequence of antibiotic activity of Schiff base is : Mo salicylioaldehyde thiadizole>Mo 3 methoxy salicylicaldehyde thiadizole>Mo piperonaldehyde thiosemicarbazone>6 nitro pieronalde thiosemicarbazone.
文摘In a completely randomized blocks (RCB) plot, we planted seed from the three segments of Kponan tubers: head, median and tail portions with control Krengle. Germination began 10 d and lasted 67 d. The mean sprouting rate of the Kponan full season harvest tuber was 78.1% compared to 94% in Krengle. However, the tuber germination was progressive from head to tail with a linear evolution of the top fragments with sprouting rate up to 90% similar to Krengle. The median and distal portions sprout two and three weeks later with final raising rates reaching 68% and 71%, respectively. The full season tuber of Kponan sprouts with a good rate gave good yields for any portion of the tuber. It had a sprouting gradient oriented from the proximal portion to the distal one, while yield was better for medium seeds. The sprouting delays two weeks between proximal and medium portions and three weeks between proximal and distal portions were acceptable with regards to the total cycle of eight to nine months period. Thus, its small tubers could be planted as well as the top portion of big tuber. In terms of yield, Kponan medium seed gave the best yield 34.25 t/ha and the whole Kponan tuber yield was more than Krengle. That led to a better multiplication factor for Kponan full season tuber. The type of tuber, if available, could be used as seed for yam production. That could improve its distribution and contribute to food security.
基金Funded by the National Natural Science Foundation of China (No. 50975246)
文摘We investigated a series of novel motors and pumps with a new structure called double-stator. Double-stator can be used as pump or motor just for the working condition on demand. A certain amount of pumps or motors are formed in one shell and these subpumps or submotors can work alone or in company without influence on other pumps or moters. This kind of double-stator pumps (motors) are called multi-pumps (multi-motors). Through the analysis of multifarious connection modes of single-acting double-stator multi-pumps and multi-motors, the mathematical expressions of output flow rate, rotational speed and torque are acquired. The results indicate that different flow rates can be provided by one fixed displacement double-stator multi-pump system under the condition of an unalterable driven speed. Likewise, under the terms of a fixed input flow and without complex variable mechanisms, the functions of double speeds, multiple speeds and even differential connection can be realized by a double-stator multi-motor system with various output rotational speeds and torques.
文摘Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and kerogens.The characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A trend.Important similarities and differences are observed between the TF profile values of the two datasets.The similarities support the spread of E-A values involved in shale pyrogram best fits.The differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions simulated.The results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A values.In contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale formations.TF profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.
基金supported by the Shenzhen Overseas High-Level Talents Innovation Funds Peacock Plan Project (No. KQCX20120814155347053)the National Natural Science Foundation of China (No. 51108242)
文摘Nitrous oxide(N_2O) is a potent greenhouse gas that can be emitted during biological nitrogen removal. N_2O emission was examined in a multiple anoxic and aerobic process at the aeration rates of 600 m L/min sequencing batch reactor(SBRL) and 1200 m L/min(SBRH).The nitrogen removal percentage was 89% in SBRLand 71% in SBRH, respectively. N_2O emission mainly occurred during the aerobic phase, and the N_2O emission factor was 10.1%in SBRLand 2.3% in SBRH, respectively. In all batch experiments, the N_2O emission potential was high in SBRLcompared with SBRH. In SBRL, with increasing aeration rates, the N_2O emission factor decreased during nitrification, while it increased during denitrification and simultaneous nitrification and denitrification(SND). By contrast, in SBRHthe N_2O emission factor during nitrification, denitrification and SND was relatively low and changed little with increasing aeration rates. The microbial competition affected the N_2O emission during biological nitrogen removal.
文摘Subject Code:D05Under support of the National Natural Science Foundation of China,a concerted study by Dr.Huang Gang(黄刚)from the Institute of Atmospheric Physics,Chinese Academy of Sciences,climate scientist Jing-Jia Luo from the Australian Bureau of Meteorology,Dr.Yao Shuailei(姚帅磊)from the Institute
文摘Objective To study the effect of patient age, the number and quality of embryos transferred on pregnancy outcome in in vitro fertilization-embryo transfer procedures (IVF-ETs). Methods A retrospective study was conducted with infertile women who underwent a total of 1 800 cycles of lVF-ET and intracytoplasmic sperm injection (ICSI) at the Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical College from Jan. 2006 to Dec. 2007. The patients were divided into three groups based on age (year). 〈30, 30-34 and 235. The rates of clinical pregnancy and multiple pregnancies were compared in each group when 1-3 embryos and 0-3 goodquality embryos were transferred respectively. Results 1) In the group of patients aged 〈30 years, there was no significant difference in pregnancy outcomes with 1-3 embryos transferred. However, pregnancy rates were similar when 2 3 good-quality embryos were transferred, which was significantly higher compared with 0-1 good-quality embryos transferred; the incidence of multiple pregnancies was not an issue when only 1 embryo was transferred. 2) The pregnancy rate of the patients aged 30 34 was not significant not only when only 2-3 embryos were transferred but also when 2-3 good-quality embryos were transferred, which was significant compared with when 1 embryo or 0 1 good-quality embryo was transferred. The subgroup of 3 good-quality embryos transferred, at the same time, was expected to significantly increase multiple pregnancy rate. 3) For the patients aged 235, there were similar pregnancy rates in the subgroup involving 1-3 embryos transferred. Compared with 0-2 good-quality embryos transferred, the pregnancy rate was significantly higher in the patients with 3 good-quality embryos transferred. An increased trend toward multiple pregnancies was observed among not only the subgroups with 1-3 embryos transferred, but also when 1-3 good-quality embryos were transferred, although it was significantly higher in patients with 3 good-quality embryo transferred. Conclusion In an effort to achieve the ideal pregnancy rate without the risk of multiple pregnancies, it is desirable to employ a single good-quality embryo transfer for patients aged 〈30 years and 2 good-quality embryos for patients aged 330. As older women (aged 335 years), this is important, need to abstain from poor-quality embryo transferred by increasing the number of embryos transferred in an effort to improve the rate of clinical pregnancy, if the patients have had enough 2 high-quality embryos.