Different amounts of absolute ethanol(0-50 mL)are used as process control agents(PCA)to prepare FeCoNiAlCr0.9 high entropy alloy(HEA)powders via 90 h ball milling.The results show that the increased amount of PCA play...Different amounts of absolute ethanol(0-50 mL)are used as process control agents(PCA)to prepare FeCoNiAlCr0.9 high entropy alloy(HEA)powders via 90 h ball milling.The results show that the increased amount of PCA plays an active role in the crystallinity of powders,and regulate the thickness and size distribution of flake particles.As the volume of PCA increases,the real and imaginary parts(ε′andε″)of complex permittivity get increased by the enhancement of the interface polarization and surface polarization,while the increase in the real and imaginary parts(μ′andμ″)of complex permeability arises from the increased anisotropic energy.The addition of PCA not only promotes the reflection loss but also extends the effective bandwidth(up to 4.28 GHz).Here,the performance adjustment of HEA electromagnetic absorber is realized by forthrightly changing the process parameters of ball milling.展开更多
A large amount of residue from the water treatment process has gradually accumulated and thus caused serious environmental pollution in waterflood oilfields. The water treatment residue is a grey suspension, with a de...A large amount of residue from the water treatment process has gradually accumulated and thus caused serious environmental pollution in waterflood oilfields. The water treatment residue is a grey suspension, with a density of 1.08 g/cm^3, and mainly contains over 65% of light CaCO3, MgCO3, CaSO4, Fe2S3 and Ca（OH）2. This paper ascertains the effect of water treatment residue on core permeability and its application in oilfields. Coreflooding tests in laboratory were conducted in two artificial cores and one natural core. Core changes were evaluated by cast model image analysis, mercury injection method and scanning electron microscopy （SEM）. Fresh water was injected into another natural core, which was plugged with water treatment residue, to determine the effective life. The results indicate that the water treatment residue has a strongly plugging capability, a resistance to erosion and a long effective life, and thus it can be used as a cheap raw material for profile control. In the past 8 years, a total of 60,164 m^3 of water treatment residue has been used for profile control of 151 well treatments, with a success ratio of 98% and an effective ratio of 83.2%. In the field tests, the profile control agent increased both starting pressure and injection pressure of injectors, and decreased the apparent water injectivity coefficient, significantly improving intake profiles and lengthening average service life of injectors. 28,381 tons of additional oil were recovered from these corresponding oil wells, with economic benefits of ￥3,069.55×10^4 （RMB） and a remarkable input-output ratio of 8.6：1.展开更多
The influence of process control agents （PCAs） on the mechanical properties of Ni3AI intermetallic compounds by mechanical alloying was investigated in order to develop oxide deposition reinforced intermetallics. Th...The influence of process control agents （PCAs） on the mechanical properties of Ni3AI intermetallic compounds by mechanical alloying was investigated in order to develop oxide deposition reinforced intermetallics. The PCAs in mechanical alloying were pure ligroin, 75 vol.% ligroin ＋ 25 vol.% alcohol, 50 vol.% ligroin ＋ 50 vol.% alcohol, 25 vol.% ligroin ＋ 75 vol.% alcohol, and pure alcohol. The normal composition is Ni-22.9at.%Al-0.5at.%B, the ball-to-powder weight ratio is 10：1, and the milling time is 30 min. Then, the powders were sintered by spark plasma sintering under 40 MPa for 5 min at 1000℃. The results show that a higher bending strength and a higher hardness were obtained when the PCAs were 75% ligroin ＋ 25% alcohol in mechanical alloying. The bending strength is about 2700 MPa and the hardness （HV） is more than 6 GPa.展开更多
In the acid fracturing of naturally fractured carbonate reservoirs,excessive acid leak off is the main factor limiting fracture propagation and live acid penetration distance.To reduce acid leakage and enhance the sti...In the acid fracturing of naturally fractured carbonate reservoirs,excessive acid leak off is the main factor limiting fracture propagation and live acid penetration distance.To reduce acid leakage and enhance the stimulation effect,ceramsite loss control agents have been widely applied in acid fracturing.However,the leak off reduction behavior of ceramsite has not yet been systematically investigated.Therefore,a conventional core-flooding acidizing system with a hollowed-out Hastelloy cylinder was used to perform a series of acid leak off experiments.Experimental results show that 1.the smaller the size of the ceramsite,the better thefiltration reduction effect;2.the higher the injection rate,the greater the acid carrying capacity,which is conducive to the loss of the control agent entering the fracture and acid-etched grooves;and 3.under laboratory conditions,the optimal ceramsite dosage is 4 g.This study deepens the understanding of acid leak off in carbonate reservoirs and provides fundamental information forfield acid fracturing design.展开更多
A method for the treatment of hazardous waste drilling fluids,potentially leading to environmental pollution,is considered.The waste drilling fluid is treated with an inorganic flocculant,an organic flocculant,and a p...A method for the treatment of hazardous waste drilling fluids,potentially leading to environmental pollution,is considered.The waste drilling fluid is treated with an inorganic flocculant,an organic flocculant,and a pH regulator.The profile control agent consists of partially hydrolyzed polyacrylamide,formaldehyde,hexamethylenetetramine,resorcinol,phenol,and the treated waste drilling fluid itself.For a waste drilling fluid concentration of 2500 mg/L,the gelling time of the profile control agent is 25 h,and the gelling strength is 32,000 mPa.s.Compared with the profile control agent prepared by recirculated water under the same conditions,the present profile control agent displays better stability,salt-resistance,and performance.展开更多
The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for BCAs.It considers the twomain categories o...The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for BCAs.It considers the twomain categories of biological control:classical and augmentative.Allowing access to BCAs for use inanother country imposes no risk of liability to the source country.Local scientific knowledge abouthabitats,fauna andflora,can be展开更多
Biological control(biocontrol) is a safe, sustainable approach that takes advantage of natural enemies such as predators, parasitic insects or pathogens to manage pests in agroecosystems. Parasitoid wasps, a very larg...Biological control(biocontrol) is a safe, sustainable approach that takes advantage of natural enemies such as predators, parasitic insects or pathogens to manage pests in agroecosystems. Parasitoid wasps, a very large evolutionary group of hymenopteran insects, are well-known biological control agents for arthropod pests in agricultural and forest ecosystems. Here, we summarize the recent progress on the application of parasitoid wasps in biocontrol in China for the last five years. These include species diversity of parasitoid wasps, identification of dominant parasitoid wasps associated with insect pests and biocontrol practices(three types of biological control, i.e., classical, augmentative and conservation biological control) in several Chinese agroecosystems. We then treat different mass-rearing and release technologies and the commercialization of several parasitoid wasp species. We also summarize other work that may have a potential use in biocontrol, including the effect of plant volatiles on parasitoids and recent advance in the molecular mechanisms underlying the host regulation by parasitoid wasps. Future research area and applied perspectives are also discussed, noting that advances in biocontrol technologies in Chinese agriculture informs research at the global level.展开更多
Most of the mining method of domestic oilfield is waterflood development, thus the water content in the mid and late water flooding would rise faster, and the oil recovery rate would decline relatively more rapid. So ...Most of the mining method of domestic oilfield is waterflood development, thus the water content in the mid and late water flooding would rise faster, and the oil recovery rate would decline relatively more rapid. So it is very important to research profile control agent for stabilizing oil production resin-type profile control agent, and focus on researching the themal stability, shear resistance, gelation time and gelation strength and other properties of this profile control agent?[1]. Finally, the best ratio for synthesizing the high temperature resistant phenolic resin-type profile control agent was obtained.展开更多
Fungi and bacteria as insecticides have been tested to control forest pests for more than ten years, they are the saine kind of biocontrol agent with the different conentrations. thesame kind of the biocontrol agent w...Fungi and bacteria as insecticides have been tested to control forest pests for more than ten years, they are the saine kind of biocontrol agent with the different conentrations. thesame kind of the biocontrol agent with the different origin areas, and the mixtures of the different kinds of biocontrol agents. The infection mechanism of virus was discussed. moreover. the mfluence of these biocontrol agents on the small animals was also evaluated.展开更多
The low-permeability oil and gas resources of our country are quite common and abundant. Their reserve has accounted for one-fifth of total oil reserves of our country, and their yield has constituted the important pa...The low-permeability oil and gas resources of our country are quite common and abundant. Their reserve has accounted for one-fifth of total oil reserves of our country, and their yield has constituted the important part of national petroleum annual yield, but its development is very difficult. Polymer gel technology is a technical method of improving sweep efficiency in recent years which substantially increases the viscosity of the polymer solution by adding a crosslinking agent to the polymer produced by intramolecular or intermolecular crosslinking.展开更多
Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical a...Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.展开更多
Various microorganisms live in association with different parts of plants and can be harmful,neutral,or beneficial to plant health.Some microbial inhabitants of plants can control plant diseases by contesting with,pre...Various microorganisms live in association with different parts of plants and can be harmful,neutral,or beneficial to plant health.Some microbial inhabitants of plants can control plant diseases by contesting with,predating on,or antagonizing plant pathogens and by inducing systems for plant defense.A range of methods,including plant growth-promoting microorganisms(PGPMs)as biological control agents(BCAs)(BCA-PGPMs)are used for the biological management and control of plant pathogens.Some BCAs interact with plants by inducing resistance or priming plants without direct interaction with the pathogen.Other BCAs operate via nutrient competition or other mechanisms to modulate the growth conditions for the pathogen.Generally,PGPMs can be applied alone or together with other chemicals or carriers to control various crop diseases.This review highlights the effective types of BCA-PGPMs and their applications,roles,carrier based-formulations,and responses to rice(Oryza sativa L.)pathogens.Future plant disease management prospects are promising,and growers’increasing demand for BCA-PGPM products can be exploited as an effective approach to the management of plant diseases,as well as to improve yield,environmental protection,biological resources,and agricultural system sustainability.展开更多
[Objectives]The paper was to effectively prevent and control the damage of Spodoptera frugiperda and to screen effective agents.[Methods]The block test of drug control was carried out,and the insect pest situation was...[Objectives]The paper was to effectively prevent and control the damage of Spodoptera frugiperda and to screen effective agents.[Methods]The block test of drug control was carried out,and the insect pest situation was investigated five times.[Results]150 mL/hm^(2) of 5%emamectin benzoate+600 mL/hm 2 of 5%lufenuron had better comprehensive control effect on S.frugiperda,and the corn yield reached 10100.55 kg/hm^(2).[Conclusions]The study provides a basis for scientific control of S.frugiperda.展开更多
Using maize varieties including Zhengdan 958,Xianyu 335,Yudan 132,Xundan 20,Lianchuang 808,and Dingyou 163 as experimental materials,this study investigated the effects of two ethephon compound agents on the lodging r...Using maize varieties including Zhengdan 958,Xianyu 335,Yudan 132,Xundan 20,Lianchuang 808,and Dingyou 163 as experimental materials,this study investigated the effects of two ethephon compound agents on the lodging resistance and yield of different maize varieties across various ecological regions.The results demonstrated that the lodging resistance of maize was significantly enhanced after the application of the two chemical control agents.Specifically,the lodging rate of Xundan 20 was reduced by 6.1 percentage points following treatment with benzylaminopurine(6-BA)·ethephon(ETH),while the lodging rate of Zhengdan 958 was decreased by 6.2 percentage points after treatment with diethyl aminoethyl hexanoate(DTA-6)·ETH.In the Shangqiu area,treatment of Lianchuang 808 with DTA-6·ETH reduced its ear height coefficient by 9.8 percentage points,whereas in the Zhumadian area,treatment of Dingyou 163 with 6-BA·ETH lowered its ear height coefficient by 11.3 percentage points.Additionally,both ethephon compound agents improved the stalk puncture strength of maize.For the same maize variety,phenotypic traits such as ear length,ear diameter,and number of kernel rows showed no significant differences under different chemical control treatments.However,traits including kernel number per row,1000-kernel weight,and yield exhibited significant variations across treatments and years.Moreover,the yield performance of maize varieties after chemical control treatment varied by region.In Hebi,Zhoukou,and Zhumadian areas,the yield under the DTA-6·ETH treatment surpassed that under the 6-BA·ETH treatment,with average yield increases of 4.22%,8.41%,and 5.67%compared to the clear water control(CK),respectively.Conversely,in Shangqiu,Nanyang,and Changge areas,the 6-BA·ETH treatment outperformed DTA-6·ETH,resulting in average yield increases of 6.96%,7.54%,and 5.56%relative to CK.展开更多
Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes tra...Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system （MAS） is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study.展开更多
Most seed gums have been widely used in oral and topical pharmaceutical formulations, cosmetics, and food products because of their hydrophilic properties. Gums from Tamariudus indica and Cassia fistula seeds were che...Most seed gums have been widely used in oral and topical pharmaceutical formulations, cosmetics, and food products because of their hydrophilic properties. Gums from Tamariudus indica and Cassia fistula seeds were chemically modified by carboxymethylation to improve their functionalities. The objective of the present study was to characterize and evaluate crude and carboxymethylated gums from T. indica and C. fistula seeds to achieve the controlled-release of diclofenac sodium(DS) in matrix tablet form. Both crude and carboxymethylated gums were characterized by Fourier transform infrared spectroscopy, Xray diffraction, and scanning electron microscopy. The results revealed that the gums were successfully modified by carboxymethylation and that the modified gums were amorphous in structure and had better flow properties. The carboxymethylated gums from both plant seeds did not exhibit cytotoxicity at concentrations lower than 0.5 mg/ml. All gum samples used as polymeric controlled-release agents were formulated into DS matrix tablets. Hardness and thickness tests were conducted as in-process tests. Drug content estimation and in vitro drug release studies were carried out to evaluate the matrix tablets. Increasing the concentration of gums increased compression time and hardness while it reduced the thickness. Furthermore, the results fitted well with the Korsmeyer–Peppas model. Moreover, the DS tablets were found to release the drug by super case II transport(relaxation). In summary, the carboxymethylated gum from T. indica and C. fistula seeds is an excellent, naturally sourced gum with high physicochemical and functional qualities, and can potentially be used in pharmaceutical applications as a disintegrant, diluent, and drug release-controlling agent.展开更多
We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-o...We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-order and second-order multi-agent systems is discussed. Furthermore, based on graph theory and stability theory, some sufficient conditions for the stability of SLCC on multi-agent systems are obtained. Finally, several numerical examples are given to verify the correctness of our theoretical results.展开更多
Heavy oil will play an important role in future resources exploitation.Factors such as reservoir heterogeneity and adverse oil/steam mobility ratio have led to severe steam channeling and fingering,thereby reduced con...Heavy oil will play an important role in future resources exploitation.Factors such as reservoir heterogeneity and adverse oil/steam mobility ratio have led to severe steam channeling and fingering,thereby reduced conformance efficiency and affected de-velopment response.Therefore,the research on profile control and water shut-off agents becomes increasingly important for thermal recovery wells.The requirements on the performances of profile control and water shut-off agents are discussed in conjunction with the physical properties of heavy oil reservoirs and the technical conditions of steam injection in China.Based on the mechanism of action,research progress and application status,5 agents are summarized including polymer gel,solid particles plugging agent,foam,water-in-oil emulsion and salt precipitation.Problems in each agent are mentioned,and optimization solutions are put for-ward.At last,the development trend of future profile control and water shut-off agents is put forward,i.e.synthesizing agents of low cost and high-temperature resistance,intensifying mechanism research,developing composite system,and researching on new technologies that are less harmful and environmental friendly.展开更多
The experiment on control of Lymantria dispar L by using different kinds ofbiological measures, including nuclear polyhedrosis virus (NPV) of Lymantria dispar L., BtMP-342,sex-attractant as well as botanical insectici...The experiment on control of Lymantria dispar L by using different kinds ofbiological measures, including nuclear polyhedrosis virus (NPV) of Lymantria dispar L., BtMP-342,sex-attractant as well as botanical insecticide, was carried out in the forest regions of InnerMongolia in 2003. Two concentrations (2.632x10^6 PIB ? ml^(-1) and 2.632x10^7 PIB ?ml^(-1)) of Lymantria dispar L. NPV were sprayed on the 2rd-instar-larvae of L. dispar and 70% and77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instarlarvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific ForestryResearch Center also showed a good result in trapping L. dispar adults. The self-produced botanicalinsecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains,China, exhibited a good control result in controlling the larvae of L. dispar, and 82% mortalitywas observed when spraying primary liquid of the botanical insecticide on the 3rd-5th-instar-larvaein lab.展开更多
基金the National Natural Science Foundation of China(Nos.51577021 and U1704253)the National Key R&D Program of China(No.2017YFB0703103)the Fundamental Research Funds for the Central Universities(No.DUT20GF111)。
文摘Different amounts of absolute ethanol(0-50 mL)are used as process control agents(PCA)to prepare FeCoNiAlCr0.9 high entropy alloy(HEA)powders via 90 h ball milling.The results show that the increased amount of PCA plays an active role in the crystallinity of powders,and regulate the thickness and size distribution of flake particles.As the volume of PCA increases,the real and imaginary parts(ε′andε″)of complex permittivity get increased by the enhancement of the interface polarization and surface polarization,while the increase in the real and imaginary parts(μ′andμ″)of complex permeability arises from the increased anisotropic energy.The addition of PCA not only promotes the reflection loss but also extends the effective bandwidth(up to 4.28 GHz).Here,the performance adjustment of HEA electromagnetic absorber is realized by forthrightly changing the process parameters of ball milling.
文摘A large amount of residue from the water treatment process has gradually accumulated and thus caused serious environmental pollution in waterflood oilfields. The water treatment residue is a grey suspension, with a density of 1.08 g/cm^3, and mainly contains over 65% of light CaCO3, MgCO3, CaSO4, Fe2S3 and Ca（OH）2. This paper ascertains the effect of water treatment residue on core permeability and its application in oilfields. Coreflooding tests in laboratory were conducted in two artificial cores and one natural core. Core changes were evaluated by cast model image analysis, mercury injection method and scanning electron microscopy （SEM）. Fresh water was injected into another natural core, which was plugged with water treatment residue, to determine the effective life. The results indicate that the water treatment residue has a strongly plugging capability, a resistance to erosion and a long effective life, and thus it can be used as a cheap raw material for profile control. In the past 8 years, a total of 60,164 m^3 of water treatment residue has been used for profile control of 151 well treatments, with a success ratio of 98% and an effective ratio of 83.2%. In the field tests, the profile control agent increased both starting pressure and injection pressure of injectors, and decreased the apparent water injectivity coefficient, significantly improving intake profiles and lengthening average service life of injectors. 28,381 tons of additional oil were recovered from these corresponding oil wells, with economic benefits of ￥3,069.55×10^4 （RMB） and a remarkable input-output ratio of 8.6：1.
文摘The influence of process control agents （PCAs） on the mechanical properties of Ni3AI intermetallic compounds by mechanical alloying was investigated in order to develop oxide deposition reinforced intermetallics. The PCAs in mechanical alloying were pure ligroin, 75 vol.% ligroin ＋ 25 vol.% alcohol, 50 vol.% ligroin ＋ 50 vol.% alcohol, 25 vol.% ligroin ＋ 75 vol.% alcohol, and pure alcohol. The normal composition is Ni-22.9at.%Al-0.5at.%B, the ball-to-powder weight ratio is 10：1, and the milling time is 30 min. Then, the powders were sintered by spark plasma sintering under 40 MPa for 5 min at 1000℃. The results show that a higher bending strength and a higher hardness were obtained when the PCAs were 75% ligroin ＋ 25% alcohol in mechanical alloying. The bending strength is about 2700 MPa and the hardness （HV） is more than 6 GPa.
基金supported by the National Sci-ence and Technology Major Projects of China(Grant No.2016ZX05014-005)Open Fund of Sinopec Key Labora-tory of Marine Reservoir Development(GSYKY-B09-32,Study on coupling effect of seepage and acid-etched in acid treatment for ShunBei naturally fractured carbonate reservoir).
文摘In the acid fracturing of naturally fractured carbonate reservoirs,excessive acid leak off is the main factor limiting fracture propagation and live acid penetration distance.To reduce acid leakage and enhance the stimulation effect,ceramsite loss control agents have been widely applied in acid fracturing.However,the leak off reduction behavior of ceramsite has not yet been systematically investigated.Therefore,a conventional core-flooding acidizing system with a hollowed-out Hastelloy cylinder was used to perform a series of acid leak off experiments.Experimental results show that 1.the smaller the size of the ceramsite,the better thefiltration reduction effect;2.the higher the injection rate,the greater the acid carrying capacity,which is conducive to the loss of the control agent entering the fracture and acid-etched grooves;and 3.under laboratory conditions,the optimal ceramsite dosage is 4 g.This study deepens the understanding of acid leak off in carbonate reservoirs and provides fundamental information forfield acid fracturing design.
文摘A method for the treatment of hazardous waste drilling fluids,potentially leading to environmental pollution,is considered.The waste drilling fluid is treated with an inorganic flocculant,an organic flocculant,and a pH regulator.The profile control agent consists of partially hydrolyzed polyacrylamide,formaldehyde,hexamethylenetetramine,resorcinol,phenol,and the treated waste drilling fluid itself.For a waste drilling fluid concentration of 2500 mg/L,the gelling time of the profile control agent is 25 h,and the gelling strength is 32,000 mPa.s.Compared with the profile control agent prepared by recirculated water under the same conditions,the present profile control agent displays better stability,salt-resistance,and performance.
文摘The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for BCAs.It considers the twomain categories of biological control:classical and augmentative.Allowing access to BCAs for use inanother country imposes no risk of liability to the source country.Local scientific knowledge abouthabitats,fauna andflora,can be
基金supported by the Key Program(31630060)Fund for Excellent Young Scholars(31230068)General Program(31672079 and 31501700) of the National Natural Science Foundation of China
文摘Biological control(biocontrol) is a safe, sustainable approach that takes advantage of natural enemies such as predators, parasitic insects or pathogens to manage pests in agroecosystems. Parasitoid wasps, a very large evolutionary group of hymenopteran insects, are well-known biological control agents for arthropod pests in agricultural and forest ecosystems. Here, we summarize the recent progress on the application of parasitoid wasps in biocontrol in China for the last five years. These include species diversity of parasitoid wasps, identification of dominant parasitoid wasps associated with insect pests and biocontrol practices(three types of biological control, i.e., classical, augmentative and conservation biological control) in several Chinese agroecosystems. We then treat different mass-rearing and release technologies and the commercialization of several parasitoid wasp species. We also summarize other work that may have a potential use in biocontrol, including the effect of plant volatiles on parasitoids and recent advance in the molecular mechanisms underlying the host regulation by parasitoid wasps. Future research area and applied perspectives are also discussed, noting that advances in biocontrol technologies in Chinese agriculture informs research at the global level.
文摘Most of the mining method of domestic oilfield is waterflood development, thus the water content in the mid and late water flooding would rise faster, and the oil recovery rate would decline relatively more rapid. So it is very important to research profile control agent for stabilizing oil production resin-type profile control agent, and focus on researching the themal stability, shear resistance, gelation time and gelation strength and other properties of this profile control agent?[1]. Finally, the best ratio for synthesizing the high temperature resistant phenolic resin-type profile control agent was obtained.
文摘Fungi and bacteria as insecticides have been tested to control forest pests for more than ten years, they are the saine kind of biocontrol agent with the different conentrations. thesame kind of the biocontrol agent with the different origin areas, and the mixtures of the different kinds of biocontrol agents. The infection mechanism of virus was discussed. moreover. the mfluence of these biocontrol agents on the small animals was also evaluated.
文摘The low-permeability oil and gas resources of our country are quite common and abundant. Their reserve has accounted for one-fifth of total oil reserves of our country, and their yield has constituted the important part of national petroleum annual yield, but its development is very difficult. Polymer gel technology is a technical method of improving sweep efficiency in recent years which substantially increases the viscosity of the polymer solution by adding a crosslinking agent to the polymer produced by intramolecular or intermolecular crosslinking.
文摘Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.
基金Raiganj University,IndiaInstituto Tecnológico de Sonora,México+7 种基金Campo Experimental Norman E.Borlaug-Instituto Nacional de Investigaciones Forestales,Agrícolas y Pecuarias(INIFAP),MéxicoUniversidad Nacional Experimental del Táchira,VenezuelaFederal University of Pernambuco,BrazilFederal University of Agriculture,NigeriaUniversity of Tabriz,IranIndian Council of Agricultural Research(ICAR)-National Rice Research Institute for supportthe Government of West Bengal,India for the Swami Vivekananda Merit Cum Means Ph.D.Scholarship(No.WBP191584588825)the Department of Science and Technology(DST),India for Inspire Fellowship(No.IF190457)。
文摘Various microorganisms live in association with different parts of plants and can be harmful,neutral,or beneficial to plant health.Some microbial inhabitants of plants can control plant diseases by contesting with,predating on,or antagonizing plant pathogens and by inducing systems for plant defense.A range of methods,including plant growth-promoting microorganisms(PGPMs)as biological control agents(BCAs)(BCA-PGPMs)are used for the biological management and control of plant pathogens.Some BCAs interact with plants by inducing resistance or priming plants without direct interaction with the pathogen.Other BCAs operate via nutrient competition or other mechanisms to modulate the growth conditions for the pathogen.Generally,PGPMs can be applied alone or together with other chemicals or carriers to control various crop diseases.This review highlights the effective types of BCA-PGPMs and their applications,roles,carrier based-formulations,and responses to rice(Oryza sativa L.)pathogens.Future plant disease management prospects are promising,and growers’increasing demand for BCA-PGPM products can be exploited as an effective approach to the management of plant diseases,as well as to improve yield,environmental protection,biological resources,and agricultural system sustainability.
文摘[Objectives]The paper was to effectively prevent and control the damage of Spodoptera frugiperda and to screen effective agents.[Methods]The block test of drug control was carried out,and the insect pest situation was investigated five times.[Results]150 mL/hm^(2) of 5%emamectin benzoate+600 mL/hm 2 of 5%lufenuron had better comprehensive control effect on S.frugiperda,and the corn yield reached 10100.55 kg/hm^(2).[Conclusions]The study provides a basis for scientific control of S.frugiperda.
基金Supported by Hebi Comprehensive Experimental Station Project of Henan Maize Industry Technology System(Z2010-02-07)Henan Science and Technology Research Project-Creating Maize Germplasm and New Varieties Resistant to Southern Rust Suitable for the Huang-Huai-Hai Ecological Region Based on RppC Gene(242102110236)+1 种基金Henan Science and Technology Research Project-Targeted Improvement Breeding Application of ZmREX4 in Regulating Kernel Length(232102110172)Henan Key Research and Development Special Project-Breeding and Industrialization Demonstration of New Varieties of Advantageous Characteristic Crops and Aquatic Products in Henan Province(241111114300).
文摘Using maize varieties including Zhengdan 958,Xianyu 335,Yudan 132,Xundan 20,Lianchuang 808,and Dingyou 163 as experimental materials,this study investigated the effects of two ethephon compound agents on the lodging resistance and yield of different maize varieties across various ecological regions.The results demonstrated that the lodging resistance of maize was significantly enhanced after the application of the two chemical control agents.Specifically,the lodging rate of Xundan 20 was reduced by 6.1 percentage points following treatment with benzylaminopurine(6-BA)·ethephon(ETH),while the lodging rate of Zhengdan 958 was decreased by 6.2 percentage points after treatment with diethyl aminoethyl hexanoate(DTA-6)·ETH.In the Shangqiu area,treatment of Lianchuang 808 with DTA-6·ETH reduced its ear height coefficient by 9.8 percentage points,whereas in the Zhumadian area,treatment of Dingyou 163 with 6-BA·ETH lowered its ear height coefficient by 11.3 percentage points.Additionally,both ethephon compound agents improved the stalk puncture strength of maize.For the same maize variety,phenotypic traits such as ear length,ear diameter,and number of kernel rows showed no significant differences under different chemical control treatments.However,traits including kernel number per row,1000-kernel weight,and yield exhibited significant variations across treatments and years.Moreover,the yield performance of maize varieties after chemical control treatment varied by region.In Hebi,Zhoukou,and Zhumadian areas,the yield under the DTA-6·ETH treatment surpassed that under the 6-BA·ETH treatment,with average yield increases of 4.22%,8.41%,and 5.67%compared to the clear water control(CK),respectively.Conversely,in Shangqiu,Nanyang,and Changge areas,the 6-BA·ETH treatment outperformed DTA-6·ETH,resulting in average yield increases of 6.96%,7.54%,and 5.56%relative to CK.
文摘Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system （MAS） is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study.
基金the Higher Education Research Promotion-National Research Universities(HERP-NRU)for financial support under grant no.2559A10862013
文摘Most seed gums have been widely used in oral and topical pharmaceutical formulations, cosmetics, and food products because of their hydrophilic properties. Gums from Tamariudus indica and Cassia fistula seeds were chemically modified by carboxymethylation to improve their functionalities. The objective of the present study was to characterize and evaluate crude and carboxymethylated gums from T. indica and C. fistula seeds to achieve the controlled-release of diclofenac sodium(DS) in matrix tablet form. Both crude and carboxymethylated gums were characterized by Fourier transform infrared spectroscopy, Xray diffraction, and scanning electron microscopy. The results revealed that the gums were successfully modified by carboxymethylation and that the modified gums were amorphous in structure and had better flow properties. The carboxymethylated gums from both plant seeds did not exhibit cytotoxicity at concentrations lower than 0.5 mg/ml. All gum samples used as polymeric controlled-release agents were formulated into DS matrix tablets. Hardness and thickness tests were conducted as in-process tests. Drug content estimation and in vitro drug release studies were carried out to evaluate the matrix tablets. Increasing the concentration of gums increased compression time and hardness while it reduced the thickness. Furthermore, the results fitted well with the Korsmeyer–Peppas model. Moreover, the DS tablets were found to release the drug by super case II transport(relaxation). In summary, the carboxymethylated gum from T. indica and C. fistula seeds is an excellent, naturally sourced gum with high physicochemical and functional qualities, and can potentially be used in pharmaceutical applications as a disintegrant, diluent, and drug release-controlling agent.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61663006 and 11661026)the Guangxi Natural Science Foundation Program,China(Grant No.2015GXNSFBB139002)+1 种基金the Guangxi Key Laboratory of Cryptography and Information Security,China(Grant No.GCIS201612)the Innovation of GUET Graduate Education,China(Grant No.2018YJCX57)
文摘We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-order and second-order multi-agent systems is discussed. Furthermore, based on graph theory and stability theory, some sufficient conditions for the stability of SLCC on multi-agent systems are obtained. Finally, several numerical examples are given to verify the correctness of our theoretical results.
文摘Heavy oil will play an important role in future resources exploitation.Factors such as reservoir heterogeneity and adverse oil/steam mobility ratio have led to severe steam channeling and fingering,thereby reduced conformance efficiency and affected de-velopment response.Therefore,the research on profile control and water shut-off agents becomes increasingly important for thermal recovery wells.The requirements on the performances of profile control and water shut-off agents are discussed in conjunction with the physical properties of heavy oil reservoirs and the technical conditions of steam injection in China.Based on the mechanism of action,research progress and application status,5 agents are summarized including polymer gel,solid particles plugging agent,foam,water-in-oil emulsion and salt precipitation.Problems in each agent are mentioned,and optimization solutions are put for-ward.At last,the development trend of future profile control and water shut-off agents is put forward,i.e.synthesizing agents of low cost and high-temperature resistance,intensifying mechanism research,developing composite system,and researching on new technologies that are less harmful and environmental friendly.
基金This paper was supported by Natural Science Foundation of Heilongjiang Province (C0235) and Youth Foundation of Harbin City (0061218024).
文摘The experiment on control of Lymantria dispar L by using different kinds ofbiological measures, including nuclear polyhedrosis virus (NPV) of Lymantria dispar L., BtMP-342,sex-attractant as well as botanical insecticide, was carried out in the forest regions of InnerMongolia in 2003. Two concentrations (2.632x10^6 PIB ? ml^(-1) and 2.632x10^7 PIB ?ml^(-1)) of Lymantria dispar L. NPV were sprayed on the 2rd-instar-larvae of L. dispar and 70% and77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instarlarvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific ForestryResearch Center also showed a good result in trapping L. dispar adults. The self-produced botanicalinsecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains,China, exhibited a good control result in controlling the larvae of L. dispar, and 82% mortalitywas observed when spraying primary liquid of the botanical insecticide on the 3rd-5th-instar-larvaein lab.
基金Supported by National Nature Science Foundation of China （61074068, 60774009, 61034007）, and the Research Fund for the Doc- toral Program of Chinese Higher Education （200804220028）
