The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated sys...The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.展开更多
Marketing channels are an important part of the circulation of agricultural products.With the development of China s agricultural industry,the marketing channels of agricultural products are continuously innovated and...Marketing channels are an important part of the circulation of agricultural products.With the development of China s agricultural industry,the marketing channels of agricultural products are continuously innovated and optimized.Taking Liujun Lotus Root as an example,on the basis of studying the existing model of marketing channels of agricultural products,this paper analyzes the problems in the existing marketing channels of Liujun Lotus Root,and puts forward relevant strategies.展开更多
The Fuling shale gas field in China is the largest shale gas field as well as the largest of its type discovered in any Lower Paleozoic formation.In this study,the geology and production of the upper and lower gas lay...The Fuling shale gas field in China is the largest shale gas field as well as the largest of its type discovered in any Lower Paleozoic formation.In this study,the geology and production of the upper and lower gas layers in the Fuling shale gas field are evaluated in terms of structure,shale quality,fault,initial production,and estimated ultimate recovery(EUR).The shale in the lower gas layer of the Jiaoshiba anticline is a high-quality reservoir,where the space is dominated by organic pores in kerogen,and the gas content is high.The shale gas wells reveal relatively high initial production and EUR.However,the shale in the upper gas layer of the Jiaoshiba anticline has reservoir space mainly composed of clay mineral pores and organic pores within bitumen,and the gas content is low.In terms of structure,primary gas migration may occur in the upper gas layer,resulting in free gas accumulation in the structural high,where the development effects are generally better than those in the structural low.The lower gas layer in the Pingqiao anticline,is the main interval for shale gas accumulation and development due to the high-quality shale.Under the influence of faults,the efficiency of exploration wells emplaced on top of the anticline is much lower a compared with those in the flanks.The residual synclines close to the Sichuan Basin,including the Baima and Baitao anticlines,are characterized by more recent uplifts,larger area,greater distance from the deep and large faults,and early fracture closure.Therefore,we recommend that the shale gas exploration and development should be carried out preferentially in areas close to the center of the residual synclines,featuring relatively high-pressure coefficient and moderate burial depth.展开更多
Khat, Ethiopia’s largest export cash crop, is the backbone of the Ethiopian economy. However, Ethiopia has not yet fully promoted its position as the utmost producer and exporter of khat in a global market because of...Khat, Ethiopia’s largest export cash crop, is the backbone of the Ethiopian economy. However, Ethiopia has not yet fully promoted its position as the utmost producer and exporter of khat in a global market because of its different policy discourses and illegal trade issues on khat production. The life of many smallholder households relies on khat production and its marketing in a country. Hence for thus, some information has been gathered on different aspects of khat with the objectives of reviewing khat’s impacts on the livelihood of smallholder farmers, its production status, and marketing constraints in Ethiopia. To review these objectives, data from CSA, and different published materials on khat were used. According to the review, khat production has a positive impact on securing household food insecurity and improving the livelihood status of smallholder farmers, and the largest foreign exchange-earning cash crops. However, it is exploited almost in all parts of a country’s government policy discourse on khat production and its trade legal issues, lack of infrastructure, zero access to extension services, zero tangible value addition, inadequate technology transfer, and research, and price volatility because of product perishability behavior are among major constraints threatened in khat production in Ethiopia. Its vulnerable and corrupted marketing system, zero market promotion and political dichotomy, long market chain, chronic market information, and unfair price were reported by different scholars as major problems of khat marketing in Ethiopia. From these probs: The government should analyze why and its impact on khat production discourse policy on the livelihood of smallholder households and overlook positive policy proclamation. Encouraging research and technology transfer to transform products into manufacturing industries, enhancing infrastructural and institutional facilities, and improving khat production product technologies through development, and khat production agribusiness industry transformation, institutionalizing its marketing arrangement and other related agronomic practices are among the major recommendations to forward so.展开更多
As a kind of clean energy which creates little carbon dioxide, natural gas will play a key role in the process of achieving “Peak Carbon Dioxide Emission” and “Carbon Neutrality”. The Long-range Energy Alternative...As a kind of clean energy which creates little carbon dioxide, natural gas will play a key role in the process of achieving “Peak Carbon Dioxide Emission” and “Carbon Neutrality”. The Long-range Energy Alternatives Planning System(LEAP) model was improved by using new parameters including comprehensive energy efficiency and terminal effective energy consumption. The Back Propagation(BP) Neural Network–LEAP model was proposed to predict key data such as total primary energy consumption, energy mix, carbon emissions from energy consumption, and natural gas consumption in China. Moreover, natural gas production in China was forecasted by the production composition method. Finally, based on the forecast results of natural gas supply and demand, suggestions were put forward on the development of China’s natural gas industry under the background of “Dual Carbon Targets”. The research results indicate that under the background of carbon peak and carbon neutrality, China’s primary energy consumption will peak(59.4×10^(8)tce) around 2035, carbon emissions from energy consumption will peak(103.4×10^(8)t) by 2025, and natural gas consumption will peak(6100×10^(8)m^(3)) around 2040, of which the largest increase will be contributed by the power sector and industrial sector. China’s peak natural gas production is about(2800–3400)×10^(8)m^(3), including(2100–2300)×10^(8)m^(3)conventional gas(including tight gas),(600–1050)×10^(8)m^(3)shale gas, and(150–220)×10^(8)m^(3)coalbed methane. Under the background of carbon peak and carbon neutrality, the natural gas consumption and production of China will further increase, showing a great potential of the natural gas industry.展开更多
With the increasingly prominent problem of food safety,the quality traceability of characteristic agricultural products has become a pressing issue.This study focuses on the application of blockchain technology in the...With the increasingly prominent problem of food safety,the quality traceability of characteristic agricultural products has become a pressing issue.This study focuses on the application of blockchain technology in the traceability of characteristic agricultural products,aiming to explore its potential and practical value in improving the efficiency and transparency of the traceability system of agricultural products.Through the combination of case analysis and model construction,a blockchain-based traceability system for characteristic agricultural products was established.The results showed that the traceability system could effectively record the whole process information of agricultural products from production and processing to sales,and greatly improve the immutability and traceability of data.Lastly,this paper also points out that the use of blockchain technology can improve the market trust in characteristic agricultural products,provide consumers with authentic and reliable product information,and provide new technical means for the quality management of agricultural products.展开更多
The objective of this study is to identify and collect information on local agriculture products and identify local potential agriculture and livestock that can attract foreign investments. Used Stratified Random Samp...The objective of this study is to identify and collect information on local agriculture products and identify local potential agriculture and livestock that can attract foreign investments. Used Stratified Random Sampling and data was collected from both primary and secondary data (both quantitative and qualitative data. The data analyzed used qualitative and quantitative analysis. The supply chain analysis was carried out to develop a description of the value chain to identify potential high-value market areas and current and potential products in the domestic and export markets. The results of the study revealed that most farmers in the research location grow different types of crops and livestock. In particular for Aileu and Ainaro where most of the areas are up-land, therefore, horticulture crops (mustard, cabbage, carrots, and tomato) and coffee are dominated in these areas. For Manufahi, some parts are lowland areas, where most crops grown are maize, cassava, and paddy rice. The study reveals that local potential agriculture products and livestock in the municipalities of Aileu, Ainaro, and Manufahi are vegetable, coffee, maize, and paddy rice, banana, shallot, tangerine, cabbage, carrot, cattle, mung-bean, and banana. To accelerate economic growth, in these municipalities, there is a need to modernize agricultural production, requiring markets for both inputs supply and for the sale of output products. Opportunities to increase the productivity of these products are feasible and this can be done through the use of high-variety seeds and better farm management, and the government and private sector can play an important role in improving productivity as this will have a further implication in improving food security.展开更多
Small ruminant production is an essential component of agricultural activity for smallholder farmers. The aim of this study was to assess small ruminant production and marketing practices in the Harawa district of Som...Small ruminant production is an essential component of agricultural activity for smallholder farmers. The aim of this study was to assess small ruminant production and marketing practices in the Harawa district of Somali Region, Ethiopia. For the study 90 households owning small ruminant were selected from three different towns of Harawa district. Information on sheep and goat ownership patterns, production objectives, and management and production constraints were collected from 90 households using semi structured questionnaires. The available feed resources are grass species, crop aftermath and legumes species are the common ones. The average family size was 5.78 ± 0.235 persons per household. Crop-livestock farming was the commonly used farming system with (62.75%) extensive and (27.25%) semi-intensive production system. The mean total land holding was 6.08 ± 0.24 ha per HH and was significantly (P < 0.05) varied across production systems. On average, the sample households owned 46.32 ± 1.22 sheep, 38.28 ± 1.40 goat, 4.85 ± 0.43 cattle, 4.15 ± 0.54 camel, 2.18 ± 0.19 donkey and 0.53 ± 0.20 poultry. The finding shows most of the respondents kept sheep and goats for insurance as ranked first. Feed shortage was ranked first as the main constraint hindering sheep and shortage of veterinary service, drought, disease, water shortage and poor infrastructure were the other major constraints of sheep and goat production in the study area. The major production and marketing constraints in small ruminant production in the area are disease and parasite (cadho), feed and grazing land shortage, low productivity, poor veterinary service and poor of infrastructure. Therefore, it is important to use modern production systems with improved technology in the area and improve traditional system through feed supplementation and better health care. As well as improving marketing efficiency through appropriate policy and provision of information is important.展开更多
Conscious consumption is a trend that is here to stay since consumers are becoming more aware of their purchasing decision and its impact on their health & environment. To sustain in the market on the move towards...Conscious consumption is a trend that is here to stay since consumers are becoming more aware of their purchasing decision and its impact on their health & environment. To sustain in the market on the move towards sustainability and meet the demands, companies need to re-examine their footprints and incorporate green practices in their products and organization. Using eco-friendly material & processes is one of the remedies to come up with this, and bamboo is one of the most versatile, green and renewable natural resources on planet earth. Traditionally bamboo has been exploited to a large extent but cutting-edge options available for bamboo are still limited and have a scope of indulging fully in the lifestyle of people in India. The global market size of bamboo was valued at UED 53.28 billion in 2020, and it is expected to grow at compound annual growth rate of 5.7% from 2022 to 2028. There is increasing demand for sustainable construction, and furniture and handicraft products also have considerable weightage. Manny brands and craft clusters of bamboo are realizing and promoting this green quotient of bamboo to the market to attract the eco-conscious audience and trying to cope up with the advancement of sustainability, like certifications of being a green organisation. Despite the exceptional qualities of bamboo, it is considered as a marginalized material due to low production rate, high competition with the non-eco-friendly or cheaper alternatives, aesthetics and marketing gaps. There is a gap between willingness to purchase and an actual purchase when it comes to the sustainable products and marketing plays a major role in conversions. The main purpose of the research is to study and understand the product, craft, design, production processes and marketing practices of bamboo lifestyle products and how conscious consumption patterns influence the bamboo products and the industry in relevance to the sustainability. Exploratory research method was applied with the literature survey and reviewing of the research papers from the peer reviewed journals. They were classified and reviewed based on the areas relevant to the bamboo products. The research outcome revealed the research gaps and the results were discussed and presented with the perspectives of product design, conscious consumption and marketing strategies in relevant to the sustainability of bamboo lifestyle products.展开更多
This article originates from the observation that field lines are drawn using distinctive rules in magnetic field and electrostatic fields. It aims at reconciliating the definitions of these fields and thus reaching a...This article originates from the observation that field lines are drawn using distinctive rules in magnetic field and electrostatic fields. It aims at reconciliating the definitions of these fields and thus reaching a consensus on the interpretation of field lines. Our unified field definition combines three orthogonal vectors and a unique scalar value. Field lines are then defined as isovalue lines of the scalar value, rendering it simpler to interpret in both field types. Specific to our field definition is the use of square root of vector’s cross product so that all vectors have the same physical unit. This enhanced field definition also enables a more efficient calculation of Biot-Savart law. This article is the first of a series allowing the drawing of isovalue contour lines.展开更多
BZ26-6 Oilfield is a kind of deep metamorphic rock buried-hill volatile oilfield in Bohai Sea, China. Its early development plan is restricted due to the simultaneous production of oil and gas in large sections of res...BZ26-6 Oilfield is a kind of deep metamorphic rock buried-hill volatile oilfield in Bohai Sea, China. Its early development plan is restricted due to the simultaneous production of oil and gas in large sections of reservoirs, unclear understanding of formation fluid properties and uncertainty of gas-oil interface. Through theoretical research on phase recovery and experimental analysis of crude oil phase characteristics in the original formation, characteristic parameters of the equilibrium condensate gas fluid are restored and calculated. Through the superimposed phase diagram of volatile oil and condensate gas, BZ26-6 Oilfield is determined to be a volatile oil reservoir with a condensate gas cap, with formation pressure and saturation pressure of 36.1 MPa, respectively. Based on the research results of oil-gas phase behavior characteristics, the thermodynamic equations and equation of state are jointly used to solve the problem, and the content change curves of each component at different depths are drawn. Combined with the sensitivity analysis of numerical simulation, the gas-oil interface is determined to be -3726 m above sea level. The fluid phase analysis software, Fluidmodeler, is used to simulate volatile oil degassing and condensate gas separation experiments. In combination with oil and gas production data obtained through the production test, the specific oil recovery index and the specific gas recovery index are determined to be 0.408 m<sup>3</sup>/(MPa·d·m) and 1195 m<sup>3</sup>/(MPa·d·m), respectively. And the reasonable production capacity prediction is conducted on the early development of BZ26-6 Oilfield. The research results can provide a theoretical basis for the efficient development of similar complex oil and gas reservoirs.展开更多
The effects of alternating magnetic field on the corrosion morphologies, corrosion rate, and corrosion products of copper in 3.5% NaCl solution, sea water, and magnetized sea water were investigated using electrochemi...The effects of alternating magnetic field on the corrosion morphologies, corrosion rate, and corrosion products of copper in 3.5% NaCl solution, sea water, and magnetized sea water were investigated using electrochemical test, scanning electron microscopy/energy dispersive analysis system of X-ray (SEM/EDAX), and X-ray diffraction (XRD). The results show that the corrosion rate of copper in magnetized sea water is minimal. Moreover, the surface of the specimen in magnetized sea water is uniform and compact as compared with those in 3.5% NaCl solution and sea water. The corrosion products of copper in magnetized sea water are mainly Cu2O and CuCl2. However, the corrosion products in sea water are CuCl, Cu2Cl(OH)3, and FeCl3-6H2O. The electrochemical corrosion mechanisms of copper in the three media were also discussed.展开更多
Objective With the discovery of the Fuling shale gas field and the realization of commercial exploitation, the prediction of shale gas well production state has attracted wide attention of scholars at home and abroad.
Seafloor hydrothermal vent fields(SHVFs) are located in the mid-ocean ridge(MOR),backarc basin(BAB),island arc and hot-spot environments and hosted mainly by ultramafic,mafic,felsic rocks,and sediments.The hydrotherma...Seafloor hydrothermal vent fields(SHVFs) are located in the mid-ocean ridge(MOR),backarc basin(BAB),island arc and hot-spot environments and hosted mainly by ultramafic,mafic,felsic rocks,and sediments.The hydrothermal vent fluids of SHVFs have low oxygen,abnormal pH and temperature,numerous toxic compounds,and inorganic energy sources,such as sulfuric compounds,methane,and hydrogen.The geological,physical,and chemical characteristics of SHVFs provide important clues to understanding the formation and evolution of seafloor hydrothermal systems,leading to the determination of metal sources and the reconstruction of the physicochemical conditions of metallogenesis.Over the past two decades,we studied the geological settings,volcanic rocks,and hydrothermal products of SHVFs and drawn new conclusions in these areas,including:1) the hydrothermal plumes in the Okinawa Trough are affected by the Kuroshio current;2) S and Pb in the hydrothermal sulfides from MOR are mainly derived from their host igneous rocks;3) Re and Os of vent fluids are more likely to be incorporated into Fe-and Fe-Cu sulfide mineral facies,and Os is enriched under low-temperature(<200℃) hydrothermal conditions in global SHVFs;4) compared with low-temperature hydrothermal sulfides,sulfates,and opal minerals,high-temperature hydrothermal sulfides maintain the helium(He) isotopic composition of the primary vent fluid;5) relatively low temperature(<116℃),oxygenated,and acidic environment conditions are favorable for forming a native sulfur chimney,and a "glue pudding" growth model can be used to understand the origin of native sulfur balls in the Kueishantao hydrothermal field;and 6) boron isotope from hydrothermal plumes and fluids can be used to describe their diffusive processes.The monitoring and understanding of the physical structure,chemical composition,geological processes,and diverse organism of subseafloor hydrothermal systems will be a future hot spot and frontier of submarine hydrothermal geology.展开更多
Based on the casting manufacture practice of steel slabs by CSP technology, the flow and the temperature fields of the funnel mould and the secondary cooling segment were simulated using the commercial code, CFX4. Com...Based on the casting manufacture practice of steel slabs by CSP technology, the flow and the temperature fields of the funnel mould and the secondary cooling segment were simulated using the commercial code, CFX4. Compared with other physical investigations, the correlative data of the present simulation results are in good agreement with them. Therefore, a more comprehensive survey for metallurgy characteristic of the flow and the temperature fields in CSP continuous casting process can be achieved.展开更多
The structural changes brought about by shale oil revolution have inspired this paper of which the aim is to analyze the potential asymmetries related to the determinants of crude oil production in the USA.Thus,using ...The structural changes brought about by shale oil revolution have inspired this paper of which the aim is to analyze the potential asymmetries related to the determinants of crude oil production in the USA.Thus,using a Markov-switching dynamic regression model in which parameters change when oil production moves from one regime to the other,it is found that for both oil production and oil relative importance,the regime that was dominant during the 1980s and the early 1990s when oil production in the USA was substantially high is the same regime that has once again become dominant in the decade corresponding to the shale oil revolution.Furthermore,the study reveals the existence of asymmetries in the relationship between US crude oil production and both manufacturing production and the consumer price index.Asymmetries are also found in the relationship between the relative importance US crude oil and manufacturing production.Finally,it is found that the intercept and the variance parameter also vary from one regime to the other,thus justifying the use of regime-dependent models.展开更多
Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic...Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs.展开更多
Taking the Gaoshangpu-Liuzan geothermal field in the Nanpu sag of the Bohai Bay Basin as the research object, this paper discusses the geological conditions and potential of the geothermal resources of the Guantao For...Taking the Gaoshangpu-Liuzan geothermal field in the Nanpu sag of the Bohai Bay Basin as the research object, this paper discusses the geological conditions and potential of the geothermal resources of the Guantao Formation in the study area, and introduces the development practice of geothermal energy heating in Caofeidian. The average buried depth of the Guantao Formation is 1500–2500 m, the lithology is dominated by sandy conglomerate, and the average thickness of thermal reservoir is 120–300 m. The average porosity of thermal reservoir is 28%–35%, the permeability is(600–2000)×10^(-3) μm^(2), and the temperature of thermal reservoir is 70–110 ℃. The formation has total geothermal resources of 13.79×10^(18) J, equivalent to 4.70×10^(8) t of standard coal. Based on a large amount of seismic and drilling data from oil and gas exploration, this study carried out high quality target area selection, simulation of sandstone thermal reservoir, and production and injection in the same layer. The geothermal heating project with distributed production and injection well pattern covering an area of 230×10^(4) m^(2) was completed in the new district of Caofeidian in 2018. The project has been running steadily for two heating seasons, with an average annual saving of 6.06×10^(4) t of standard coal and a reduction of 15.87×10^(4) t of carbon dioxide, achieving good economic and social benefits. This project has proved that the Neogene sandstone geothermal reservoir in eastern China can achieve sustainable large-scale development by using the technology of "balanced production and injection in the same layer". It provides effective reference for the exploration and development of geothermal resource in oil and gas-bearing basins in eastern China.展开更多
基金This study was supported by the National Natural Science Foundation ofChina(Nos.12147106,12175072,and 11722546)the Talent Programof South China University of Technology(No.20210115).
文摘The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.
文摘Marketing channels are an important part of the circulation of agricultural products.With the development of China s agricultural industry,the marketing channels of agricultural products are continuously innovated and optimized.Taking Liujun Lotus Root as an example,on the basis of studying the existing model of marketing channels of agricultural products,this paper analyzes the problems in the existing marketing channels of Liujun Lotus Root,and puts forward relevant strategies.
基金supported by the National Natural Science Foundation of China(Grant No.41872124 and 91755211)and several Sinopec in-house projects.We thank Sinopec Petroleum Exploration and Production Research Institute,Sinopec Exploration Company,Sinopec Jianghan Oilfield,and Sinopec East China Petroleum Company for valuable data and information.
文摘The Fuling shale gas field in China is the largest shale gas field as well as the largest of its type discovered in any Lower Paleozoic formation.In this study,the geology and production of the upper and lower gas layers in the Fuling shale gas field are evaluated in terms of structure,shale quality,fault,initial production,and estimated ultimate recovery(EUR).The shale in the lower gas layer of the Jiaoshiba anticline is a high-quality reservoir,where the space is dominated by organic pores in kerogen,and the gas content is high.The shale gas wells reveal relatively high initial production and EUR.However,the shale in the upper gas layer of the Jiaoshiba anticline has reservoir space mainly composed of clay mineral pores and organic pores within bitumen,and the gas content is low.In terms of structure,primary gas migration may occur in the upper gas layer,resulting in free gas accumulation in the structural high,where the development effects are generally better than those in the structural low.The lower gas layer in the Pingqiao anticline,is the main interval for shale gas accumulation and development due to the high-quality shale.Under the influence of faults,the efficiency of exploration wells emplaced on top of the anticline is much lower a compared with those in the flanks.The residual synclines close to the Sichuan Basin,including the Baima and Baitao anticlines,are characterized by more recent uplifts,larger area,greater distance from the deep and large faults,and early fracture closure.Therefore,we recommend that the shale gas exploration and development should be carried out preferentially in areas close to the center of the residual synclines,featuring relatively high-pressure coefficient and moderate burial depth.
文摘Khat, Ethiopia’s largest export cash crop, is the backbone of the Ethiopian economy. However, Ethiopia has not yet fully promoted its position as the utmost producer and exporter of khat in a global market because of its different policy discourses and illegal trade issues on khat production. The life of many smallholder households relies on khat production and its marketing in a country. Hence for thus, some information has been gathered on different aspects of khat with the objectives of reviewing khat’s impacts on the livelihood of smallholder farmers, its production status, and marketing constraints in Ethiopia. To review these objectives, data from CSA, and different published materials on khat were used. According to the review, khat production has a positive impact on securing household food insecurity and improving the livelihood status of smallholder farmers, and the largest foreign exchange-earning cash crops. However, it is exploited almost in all parts of a country’s government policy discourse on khat production and its trade legal issues, lack of infrastructure, zero access to extension services, zero tangible value addition, inadequate technology transfer, and research, and price volatility because of product perishability behavior are among major constraints threatened in khat production in Ethiopia. Its vulnerable and corrupted marketing system, zero market promotion and political dichotomy, long market chain, chronic market information, and unfair price were reported by different scholars as major problems of khat marketing in Ethiopia. From these probs: The government should analyze why and its impact on khat production discourse policy on the livelihood of smallholder households and overlook positive policy proclamation. Encouraging research and technology transfer to transform products into manufacturing industries, enhancing infrastructural and institutional facilities, and improving khat production product technologies through development, and khat production agribusiness industry transformation, institutionalizing its marketing arrangement and other related agronomic practices are among the major recommendations to forward so.
基金Supported by Project of Science and Technology of PetroChina (2021DJ17,2021DJ21)。
文摘As a kind of clean energy which creates little carbon dioxide, natural gas will play a key role in the process of achieving “Peak Carbon Dioxide Emission” and “Carbon Neutrality”. The Long-range Energy Alternatives Planning System(LEAP) model was improved by using new parameters including comprehensive energy efficiency and terminal effective energy consumption. The Back Propagation(BP) Neural Network–LEAP model was proposed to predict key data such as total primary energy consumption, energy mix, carbon emissions from energy consumption, and natural gas consumption in China. Moreover, natural gas production in China was forecasted by the production composition method. Finally, based on the forecast results of natural gas supply and demand, suggestions were put forward on the development of China’s natural gas industry under the background of “Dual Carbon Targets”. The research results indicate that under the background of carbon peak and carbon neutrality, China’s primary energy consumption will peak(59.4×10^(8)tce) around 2035, carbon emissions from energy consumption will peak(103.4×10^(8)t) by 2025, and natural gas consumption will peak(6100×10^(8)m^(3)) around 2040, of which the largest increase will be contributed by the power sector and industrial sector. China’s peak natural gas production is about(2800–3400)×10^(8)m^(3), including(2100–2300)×10^(8)m^(3)conventional gas(including tight gas),(600–1050)×10^(8)m^(3)shale gas, and(150–220)×10^(8)m^(3)coalbed methane. Under the background of carbon peak and carbon neutrality, the natural gas consumption and production of China will further increase, showing a great potential of the natural gas industry.
文摘With the increasingly prominent problem of food safety,the quality traceability of characteristic agricultural products has become a pressing issue.This study focuses on the application of blockchain technology in the traceability of characteristic agricultural products,aiming to explore its potential and practical value in improving the efficiency and transparency of the traceability system of agricultural products.Through the combination of case analysis and model construction,a blockchain-based traceability system for characteristic agricultural products was established.The results showed that the traceability system could effectively record the whole process information of agricultural products from production and processing to sales,and greatly improve the immutability and traceability of data.Lastly,this paper also points out that the use of blockchain technology can improve the market trust in characteristic agricultural products,provide consumers with authentic and reliable product information,and provide new technical means for the quality management of agricultural products.
文摘The objective of this study is to identify and collect information on local agriculture products and identify local potential agriculture and livestock that can attract foreign investments. Used Stratified Random Sampling and data was collected from both primary and secondary data (both quantitative and qualitative data. The data analyzed used qualitative and quantitative analysis. The supply chain analysis was carried out to develop a description of the value chain to identify potential high-value market areas and current and potential products in the domestic and export markets. The results of the study revealed that most farmers in the research location grow different types of crops and livestock. In particular for Aileu and Ainaro where most of the areas are up-land, therefore, horticulture crops (mustard, cabbage, carrots, and tomato) and coffee are dominated in these areas. For Manufahi, some parts are lowland areas, where most crops grown are maize, cassava, and paddy rice. The study reveals that local potential agriculture products and livestock in the municipalities of Aileu, Ainaro, and Manufahi are vegetable, coffee, maize, and paddy rice, banana, shallot, tangerine, cabbage, carrot, cattle, mung-bean, and banana. To accelerate economic growth, in these municipalities, there is a need to modernize agricultural production, requiring markets for both inputs supply and for the sale of output products. Opportunities to increase the productivity of these products are feasible and this can be done through the use of high-variety seeds and better farm management, and the government and private sector can play an important role in improving productivity as this will have a further implication in improving food security.
文摘Small ruminant production is an essential component of agricultural activity for smallholder farmers. The aim of this study was to assess small ruminant production and marketing practices in the Harawa district of Somali Region, Ethiopia. For the study 90 households owning small ruminant were selected from three different towns of Harawa district. Information on sheep and goat ownership patterns, production objectives, and management and production constraints were collected from 90 households using semi structured questionnaires. The available feed resources are grass species, crop aftermath and legumes species are the common ones. The average family size was 5.78 ± 0.235 persons per household. Crop-livestock farming was the commonly used farming system with (62.75%) extensive and (27.25%) semi-intensive production system. The mean total land holding was 6.08 ± 0.24 ha per HH and was significantly (P < 0.05) varied across production systems. On average, the sample households owned 46.32 ± 1.22 sheep, 38.28 ± 1.40 goat, 4.85 ± 0.43 cattle, 4.15 ± 0.54 camel, 2.18 ± 0.19 donkey and 0.53 ± 0.20 poultry. The finding shows most of the respondents kept sheep and goats for insurance as ranked first. Feed shortage was ranked first as the main constraint hindering sheep and shortage of veterinary service, drought, disease, water shortage and poor infrastructure were the other major constraints of sheep and goat production in the study area. The major production and marketing constraints in small ruminant production in the area are disease and parasite (cadho), feed and grazing land shortage, low productivity, poor veterinary service and poor of infrastructure. Therefore, it is important to use modern production systems with improved technology in the area and improve traditional system through feed supplementation and better health care. As well as improving marketing efficiency through appropriate policy and provision of information is important.
文摘Conscious consumption is a trend that is here to stay since consumers are becoming more aware of their purchasing decision and its impact on their health & environment. To sustain in the market on the move towards sustainability and meet the demands, companies need to re-examine their footprints and incorporate green practices in their products and organization. Using eco-friendly material & processes is one of the remedies to come up with this, and bamboo is one of the most versatile, green and renewable natural resources on planet earth. Traditionally bamboo has been exploited to a large extent but cutting-edge options available for bamboo are still limited and have a scope of indulging fully in the lifestyle of people in India. The global market size of bamboo was valued at UED 53.28 billion in 2020, and it is expected to grow at compound annual growth rate of 5.7% from 2022 to 2028. There is increasing demand for sustainable construction, and furniture and handicraft products also have considerable weightage. Manny brands and craft clusters of bamboo are realizing and promoting this green quotient of bamboo to the market to attract the eco-conscious audience and trying to cope up with the advancement of sustainability, like certifications of being a green organisation. Despite the exceptional qualities of bamboo, it is considered as a marginalized material due to low production rate, high competition with the non-eco-friendly or cheaper alternatives, aesthetics and marketing gaps. There is a gap between willingness to purchase and an actual purchase when it comes to the sustainable products and marketing plays a major role in conversions. The main purpose of the research is to study and understand the product, craft, design, production processes and marketing practices of bamboo lifestyle products and how conscious consumption patterns influence the bamboo products and the industry in relevance to the sustainability. Exploratory research method was applied with the literature survey and reviewing of the research papers from the peer reviewed journals. They were classified and reviewed based on the areas relevant to the bamboo products. The research outcome revealed the research gaps and the results were discussed and presented with the perspectives of product design, conscious consumption and marketing strategies in relevant to the sustainability of bamboo lifestyle products.
文摘This article originates from the observation that field lines are drawn using distinctive rules in magnetic field and electrostatic fields. It aims at reconciliating the definitions of these fields and thus reaching a consensus on the interpretation of field lines. Our unified field definition combines three orthogonal vectors and a unique scalar value. Field lines are then defined as isovalue lines of the scalar value, rendering it simpler to interpret in both field types. Specific to our field definition is the use of square root of vector’s cross product so that all vectors have the same physical unit. This enhanced field definition also enables a more efficient calculation of Biot-Savart law. This article is the first of a series allowing the drawing of isovalue contour lines.
文摘BZ26-6 Oilfield is a kind of deep metamorphic rock buried-hill volatile oilfield in Bohai Sea, China. Its early development plan is restricted due to the simultaneous production of oil and gas in large sections of reservoirs, unclear understanding of formation fluid properties and uncertainty of gas-oil interface. Through theoretical research on phase recovery and experimental analysis of crude oil phase characteristics in the original formation, characteristic parameters of the equilibrium condensate gas fluid are restored and calculated. Through the superimposed phase diagram of volatile oil and condensate gas, BZ26-6 Oilfield is determined to be a volatile oil reservoir with a condensate gas cap, with formation pressure and saturation pressure of 36.1 MPa, respectively. Based on the research results of oil-gas phase behavior characteristics, the thermodynamic equations and equation of state are jointly used to solve the problem, and the content change curves of each component at different depths are drawn. Combined with the sensitivity analysis of numerical simulation, the gas-oil interface is determined to be -3726 m above sea level. The fluid phase analysis software, Fluidmodeler, is used to simulate volatile oil degassing and condensate gas separation experiments. In combination with oil and gas production data obtained through the production test, the specific oil recovery index and the specific gas recovery index are determined to be 0.408 m<sup>3</sup>/(MPa·d·m) and 1195 m<sup>3</sup>/(MPa·d·m), respectively. And the reasonable production capacity prediction is conducted on the early development of BZ26-6 Oilfield. The research results can provide a theoretical basis for the efficient development of similar complex oil and gas reservoirs.
文摘The effects of alternating magnetic field on the corrosion morphologies, corrosion rate, and corrosion products of copper in 3.5% NaCl solution, sea water, and magnetized sea water were investigated using electrochemical test, scanning electron microscopy/energy dispersive analysis system of X-ray (SEM/EDAX), and X-ray diffraction (XRD). The results show that the corrosion rate of copper in magnetized sea water is minimal. Moreover, the surface of the specimen in magnetized sea water is uniform and compact as compared with those in 3.5% NaCl solution and sea water. The corrosion products of copper in magnetized sea water are mainly Cu2O and CuCl2. However, the corrosion products in sea water are CuCl, Cu2Cl(OH)3, and FeCl3-6H2O. The electrochemical corrosion mechanisms of copper in the three media were also discussed.
基金Project of National Natural Science Foundation o f China (grant No.41503033)the Key Project of National Natural Science Foundation o f China (grant No.Ul 663202)
文摘Objective With the discovery of the Fuling shale gas field and the realization of commercial exploitation, the prediction of shale gas well production state has attracted wide attention of scholars at home and abroad.
基金the National Natural Science Foundation of China(No.91958213)the National Program on Global Change and Air-Sea Interaction(No.GASI-GEOGE-02)+2 种基金the International Partnership Program of the Chinese Academy of Sciences(No.133137KYSB20170003)the Special Fund for the Taishan Scholar Program of Shandong Province(No.ts201511061)the National Key Basic Research Program of China(No.2013CB429700)。
文摘Seafloor hydrothermal vent fields(SHVFs) are located in the mid-ocean ridge(MOR),backarc basin(BAB),island arc and hot-spot environments and hosted mainly by ultramafic,mafic,felsic rocks,and sediments.The hydrothermal vent fluids of SHVFs have low oxygen,abnormal pH and temperature,numerous toxic compounds,and inorganic energy sources,such as sulfuric compounds,methane,and hydrogen.The geological,physical,and chemical characteristics of SHVFs provide important clues to understanding the formation and evolution of seafloor hydrothermal systems,leading to the determination of metal sources and the reconstruction of the physicochemical conditions of metallogenesis.Over the past two decades,we studied the geological settings,volcanic rocks,and hydrothermal products of SHVFs and drawn new conclusions in these areas,including:1) the hydrothermal plumes in the Okinawa Trough are affected by the Kuroshio current;2) S and Pb in the hydrothermal sulfides from MOR are mainly derived from their host igneous rocks;3) Re and Os of vent fluids are more likely to be incorporated into Fe-and Fe-Cu sulfide mineral facies,and Os is enriched under low-temperature(<200℃) hydrothermal conditions in global SHVFs;4) compared with low-temperature hydrothermal sulfides,sulfates,and opal minerals,high-temperature hydrothermal sulfides maintain the helium(He) isotopic composition of the primary vent fluid;5) relatively low temperature(<116℃),oxygenated,and acidic environment conditions are favorable for forming a native sulfur chimney,and a "glue pudding" growth model can be used to understand the origin of native sulfur balls in the Kueishantao hydrothermal field;and 6) boron isotope from hydrothermal plumes and fluids can be used to describe their diffusive processes.The monitoring and understanding of the physical structure,chemical composition,geological processes,and diverse organism of subseafloor hydrothermal systems will be a future hot spot and frontier of submarine hydrothermal geology.
基金Item Sponsored by Scientific Research Program Foundation of Shanghai City of China(04DZ05621)
文摘Based on the casting manufacture practice of steel slabs by CSP technology, the flow and the temperature fields of the funnel mould and the secondary cooling segment were simulated using the commercial code, CFX4. Compared with other physical investigations, the correlative data of the present simulation results are in good agreement with them. Therefore, a more comprehensive survey for metallurgy characteristic of the flow and the temperature fields in CSP continuous casting process can be achieved.
文摘The structural changes brought about by shale oil revolution have inspired this paper of which the aim is to analyze the potential asymmetries related to the determinants of crude oil production in the USA.Thus,using a Markov-switching dynamic regression model in which parameters change when oil production moves from one regime to the other,it is found that for both oil production and oil relative importance,the regime that was dominant during the 1980s and the early 1990s when oil production in the USA was substantially high is the same regime that has once again become dominant in the decade corresponding to the shale oil revolution.Furthermore,the study reveals the existence of asymmetries in the relationship between US crude oil production and both manufacturing production and the consumer price index.Asymmetries are also found in the relationship between the relative importance US crude oil and manufacturing production.Finally,it is found that the intercept and the variance parameter also vary from one regime to the other,thus justifying the use of regime-dependent models.
基金supported by grants from the National Key R&D Program of China(2016YFC0500302)the National Natural Science Foundation of China(U1808201)+1 种基金Strategic Leading Science&Technology Programme,CAS(XDA23070100)the Liaoning Revitalization Talents Program(XLYC1807102).
文摘Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs.
基金This study was supported and helped by Professor Yan Jiahong with China Petroleum Exploration and Development Research Institute,Yao Yanhua,Chief Geologist of the Hydrology Institute of PetroChina Liaohe Oilfield Company,and Dr.Kong Yanlong with the Institute of Geology and Geophysics,Chinese Academy of Sciences.
文摘Taking the Gaoshangpu-Liuzan geothermal field in the Nanpu sag of the Bohai Bay Basin as the research object, this paper discusses the geological conditions and potential of the geothermal resources of the Guantao Formation in the study area, and introduces the development practice of geothermal energy heating in Caofeidian. The average buried depth of the Guantao Formation is 1500–2500 m, the lithology is dominated by sandy conglomerate, and the average thickness of thermal reservoir is 120–300 m. The average porosity of thermal reservoir is 28%–35%, the permeability is(600–2000)×10^(-3) μm^(2), and the temperature of thermal reservoir is 70–110 ℃. The formation has total geothermal resources of 13.79×10^(18) J, equivalent to 4.70×10^(8) t of standard coal. Based on a large amount of seismic and drilling data from oil and gas exploration, this study carried out high quality target area selection, simulation of sandstone thermal reservoir, and production and injection in the same layer. The geothermal heating project with distributed production and injection well pattern covering an area of 230×10^(4) m^(2) was completed in the new district of Caofeidian in 2018. The project has been running steadily for two heating seasons, with an average annual saving of 6.06×10^(4) t of standard coal and a reduction of 15.87×10^(4) t of carbon dioxide, achieving good economic and social benefits. This project has proved that the Neogene sandstone geothermal reservoir in eastern China can achieve sustainable large-scale development by using the technology of "balanced production and injection in the same layer". It provides effective reference for the exploration and development of geothermal resource in oil and gas-bearing basins in eastern China.