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Developing Operational Model for Heat Pumps as Space Heating and Domestic Hot Water Provider
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作者 Rilwan Olaolu Oliyide Jose B. Hernandez 《Open Journal of Applied Sciences》 2024年第10期2880-2900,共21页
In the United Kingdom, means of meeting domestic heating is being electrified to decarbonise in effort to reduce the greenhouse gases emissions from the burning of natural gas. Therefore, the uptake of heat pumps is o... In the United Kingdom, means of meeting domestic heating is being electrified to decarbonise in effort to reduce the greenhouse gases emissions from the burning of natural gas. Therefore, the uptake of heat pumps is on the increase. The operation and working principle of heat pumps must be well understood in the investigations of their impacts on the grid and the grid assets, especially distribution transformers which could be overloaded due to higher peak load demand. This work develops an operational model of heat pumps as combined space heating and domestic hot water provider implemented in MATLAB. The developed operational model of heat pumps is adaptable and repeatable for different input parameters. The developed model is used to generate daily average demand profiles of heat pumps for a typical winter weekday and a typical summer weekday. The generated demand profiles of heat pumps by the developed model compared well with the demand profiles of heat pumps generated from actual field projects which are usually expensive and time-tasking. 展开更多
关键词 Heat Pumps Greenhouse Gases Space Heating Domestic hot water TRANSFORMER MATLAB
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Study on Processing of Clear Banana Juice Using Hot Water Extraction Method 被引量:2
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作者 郑欣 余元善 +4 位作者 吴继军 徐玉娟 肖更生 黄婉华 温靖 《Agricultural Science & Technology》 CAS 2014年第11期2003-2005,2044,共4页
In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat ... In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO. 展开更多
关键词 Clear banana juice hot water extraction Polyphenol oxidase Pectin Protein
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Magnetite-Fluorite Rock:A New Rock Type of Hot Water Sedimentation 被引量:6
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作者 XU Shaokang XIA Xuehui +4 位作者 YUAN Congjian WANG Bingquan YAN Fei YAN Shengxian ZHENG Xingquan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期906-910,共5页
The new type hot water sedimentary rock -- magnetite-fluorite rock occurs as quasi-layers in flat parts of contact zones between rock body and strata in Bamianshan of Changshan County, Zhejiang Province, China. The ma... The new type hot water sedimentary rock -- magnetite-fluorite rock occurs as quasi-layers in flat parts of contact zones between rock body and strata in Bamianshan of Changshan County, Zhejiang Province, China. The main mineral assemblage is fluorite+magnetite+cassiterite. The rock shows typical laminated structure and obvious mosaic texture. Its formation temperature is between 123℃-160℃, averaging at 142℃. The major chemical composition of the rock includes CaF2, SiO2, Al2O3, FeO, and Fe2O3; the high-content microelement association includes W, Sn, Be, Rb, Sr, S, and CI; and the total content of REE is low (∑REE between 35.34×10^-6-38.35×10^-6), showing LREE enrichment type of distribution pattern. Diagenesis: driven by the tectonic stress, the formation water heated in the deep strata had moved along the fissures or fractures in strata and had extracted components from the strata on the way, and finally stagnated in the flat parts of contact zones between rock body and strata. With drop in temperature, magnetite and fluorite were separated from the hot water and precipitated alternately, forming this hot water sedimentary rock with new type mineralogical composition, typical laminated structure, obvious mosaic texture and sub-horizontal occurrence. The characteristics of the new type mineralogical composition, sedimentary tectonic environment and chemical composition are different from that of the well-known traditional hydrothermai sedimentary rocks. 展开更多
关键词 magnetite-fluorite rock hot water sedimentary rock hydrothermal sedimentary rock laminated structure sedimentary tectonic environment PETROCHEMISTRY
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Energy and exergy recovery from exhaust hot water using organic Rankine cycle and a retrofitted configuration 被引量:8
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作者 SUN Wen-qiang YUE Xiao-yu +1 位作者 WANG Yan-hui CAI Jiu-ju 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第6期1464-1474,共11页
Exhaust hot water (EHW) is widely used for various industrial processes. However, the excess heat carried by EHW is typically ignored and discharged into the environment, resulting in heat loss and heat pollution. A... Exhaust hot water (EHW) is widely used for various industrial processes. However, the excess heat carried by EHW is typically ignored and discharged into the environment, resulting in heat loss and heat pollution. An organic Rankine cycle (ORC) is an attractive technology to recycle heat from low-temperature energy carriers. Herein, ORC was used to recycle the heat carried by EHW. To investigate the energy and exergy recovery effects of EHW, a mathematical model was developed and a parametric study was conducted. The energy efficiency and exergy efficiency of the EHW-driven ORC system were modeled with R245fa, Rl13 and R123 as the working fluids. The results demonstrate that the EHW and evaporation temperatures have significant effects on the energy and exergy efficiencies of the EHW-driven ORC system. Under given EHW conditions, an optimum evaporation temperature exists corresponding to the highest exergy efficiency. To further use the low-temperature EHW, a configuration retrofitted to the ORC by combining with flash evaporation (FE) was conducted. For an EHW at 120 ~C and 0.2 MPa, the maximum exergy efficiency of the FE-ORC system is 45.91% at a flash pressure of 0.088 MPa. The FE-ORC performs better in exergy efficiency than the basic FE and basic EHW-driven ORC. 展开更多
关键词 exhaust hot water (EHW) organic Rankine cycle (ORC) energy efficiency exergy efficiency flashevaporation (FE)
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Application of Cooling Water in Controlled Runout Table Cooling on Hot Strip Mill 被引量:2
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作者 LIUZheng-dong IVSamarasekera 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2004年第3期15-23,共9页
The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip.The heat of a hot steel strip is mainly extracted by cooling water during runout.In order to ... The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip.The heat of a hot steel strip is mainly extracted by cooling water during runout.In order to study the heat transfer by water jet impingement boiling during runout,apilot facility was constructed at the University of British Columbia.On this pilot facility,the water jet impingement tests were carried out under various cooling conditions to investigate the effect of processing parameters,such as cooling water temperature,water jet impingement velocity,initial strip temperature,water flow rate,water nozzle diameter and array of water nozzles,on the heat transfer of heated strip.The results obtained contribute to the optimization of cooling water during runout. 展开更多
关键词 cooling water controlled runout table hot strip mill
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IMPACT OF WATER ENVIRONMENTAL CHARACTERISTICS IN DRY-HOT VALLEY OF JINSHA RIVER ON SOIL DESERTIFICATION 被引量:1
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作者 刘刚才 刘淑珍 《Chinese Geographical Science》 SCIE CSCD 1999年第2期93-96,共4页
Based on the field investigation and the analysis of soil moisture curve, it is clearly shown that there is a positive relationship between vegetation coverage rate and soil moisture capacity and soil depth in dry ho... Based on the field investigation and the analysis of soil moisture curve, it is clearly shown that there is a positive relationship between vegetation coverage rate and soil moisture capacity and soil depth in dry hot valley of the Jinsha River, and also there is a desertification process with seasonality. It is suggested that the basic factor of desertification in the area is water deficiency (seasonal drought and low soil water capacity) and the direct dynamic of desertification is soil erosion. Some effective countermeasures are presented, of which water saving planting and irrigation techniques should be firstly applied in the studied area. 展开更多
关键词 DESERTIFICATION DRY hot VALLEY of the Jinsha RIVER water environment
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Flexibility Prediction of Aggregated Electric Vehicles and Domestic Hot Water Systems in Smart Grids 被引量:4
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作者 Junjie Hu Huayanran Zhou +3 位作者 Yihong Zhou Haijing Zhang Lars Nordströmd Guangya Yang 《Engineering》 SCIE EI 2021年第8期1101-1114,共14页
With the growth of intermittent renewable energy generation in power grids,there is an increasing demand for controllable resources to be deployed to guarantee power quality and frequency stability.The flexibility of ... With the growth of intermittent renewable energy generation in power grids,there is an increasing demand for controllable resources to be deployed to guarantee power quality and frequency stability.The flexibility of demand response(DR)resources has become a valuable solution to this problem.However,existing research indicates that problems on flexibility prediction of DR resources have not been investigated.This study applied the temporal convolution network(TCN)-combined transformer,a deep learning technique to predict the aggregated flexibility of two types of DR resources,that is,electric vehicles(EVs)and domestic hot water system(DHWS).The prediction uses historical power consumption data of these DR resources and DR signals(DSs)to facilitate prediction.The prediction can generate the size and maintenance time of the aggregated flexibility.The accuracy of the flexibility prediction results was verified through simulations of case studies.The simulation results show that under different maintenance times,the size of the flexibility changed.The proposed DR resource flexibility prediction method demonstrates its application in unlocking the demand-side flexibility to provide a reserve to grids. 展开更多
关键词 Load flexibility Electric vehicles Domestic hot water system Temporal convolution network-combined TRANSFORMER Deep learning
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Friction Behaviors of the Hot Filament Chemical Vapor Deposition Diamond Film under Ambient Air and Water Lubricating Conditions 被引量:2
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作者 SHEN Bin SUN Fanghong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期658-664,共7页
The friction behavior of the hot filament chemical vapor deposition(HFCVD) diamond film plays a critical role on its applications in mechanical fields and largely depends on the environment. Studies on the tribologi... The friction behavior of the hot filament chemical vapor deposition(HFCVD) diamond film plays a critical role on its applications in mechanical fields and largely depends on the environment. Studies on the tribological properties of HFCVD diamond films coated on Co-cemented tungsten carbide (WC-Co) substrates are rarely reported in available literatures, especially in the water lubricating conditions. In this paper, conventional microcrystalline diamond(MCD) and fine-grained diamond(FGD) films are deposited on WC-Co substrates and their friction properties are evaluated on a reciprocating ball-on-plate tribometer, where they are brought to slide against ball-bearing steel and copper balls in dry and water lubricating conditions. Scanning electron microscopy(SEM), atomic force microscopy(AFM), surface profilometer and Raman spectroscopy are adopted to characterize as-deposited diamond films; SEM and energy dispersive X-ray(EDX) are used to investigate the worn region on the surfaces of both counterface balls and diamond films. The research results show that the friction coefficient of HFCVD diamond films always starts with a high initial value, and then gradually transits to a relative stable state. For a given counterface and a sliding condition, the FGD film presents lower stable friction coefficients by 0.02-0.03 than MCD film. The transferred materials adhered on sliding interface are supposed to have predominate effect on the friction behaviors of HFCVD diamond films. Furthermore, the effect of water lubricating on reducing friction coefficient is significant. For a given counterpart, the stable friction coefficients of MCD or FGD films reduce by about 0.07-0.08 while sliding in the water lubricating condition, relative to in dry sliding condition. This study is beneficial for widespread applications of HFCVD diamond coated mechanical components and adopting water lubricating system, replacing ofoil lubricating, in a variety of mechanical processing fields to implement the green production process. 展开更多
关键词 hot filament chemical vapor deposition(HFCVD) diamond films friction behavior water lubricating
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Heating of heavy oil by circulating hot water in closed double casing in ultra-deep wells 被引量:1
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作者 Lin Riyi Wang Fangzheng Wang Xinwei 《Petroleum Science》 SCIE CAS CSCD 2012年第4期506-510,共5页
In heavy oil production,the loss of energy to ambient surroundings decreases the temperature of the heavy oil flowing upwards in a vertical wellbore,which increases the oil viscosity and the oil may not flow normally ... In heavy oil production,the loss of energy to ambient surroundings decreases the temperature of the heavy oil flowing upwards in a vertical wellbore,which increases the oil viscosity and the oil may not flow normally in the wellbore.Therefore,it is necessary to lower the heavy oil viscosity by heating methods to allow it to be lifted easily.Heating of heavy oil in an oil well is achieved by circulating hot water in annuli in the well(tubing-casing annulus,casing-casing annulus).In this paper,based on heat transfer principles and fluid flow theory,a model is developed for produced fluids and hot water flowing in a vertical wellbore.The temperature and pressure of produced fluids and hot water in the wellbore are calculated and the effect of hot water on heavy oil temperature is analyzed.Calculated results show that the hot water circulating in the annuli may effectively heat the heavy oil in the tubing,so as to significantly reduce both oil viscosity and resistance to oil flow. 展开更多
关键词 Heavy oil double casing hot water injection viscosity reduction
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Energy efficiency performance of multi-energy district heating and hot water supply system 被引量:2
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作者 金楠 赵靖 朱能 《Journal of Central South University》 SCIE EI CAS 2012年第5期1377-1382,共6页
A district heating and hot water supply system is presented which synthetically utilizes geothermal energy,solar thermal energy and natural gas thermal energy.The multi-energy utilization system has been set at the ne... A district heating and hot water supply system is presented which synthetically utilizes geothermal energy,solar thermal energy and natural gas thermal energy.The multi-energy utilization system has been set at the new campus of Tianjin Polytechnic University(TPU),A couple of deep geothermal wells which are 2 300 m in depth were dug,Deep geothermal energy cascade utilization is achieved by two stages of plate heat exchangers(PHE) and two stages of water source heat pumps(WSHP).Shallow geothermal energy is used in assistant heating by two ground coupled heat pumps(GCHPs) with 580 vertical ground wells which are 120 m in depth.Solar thermal energy collected by vacuum tube arrays(VTAs) and geothermal energy are complementarily utilized to make domestic hot water.Superfluous solar energy can be stored in shallow soil for the GCHP utilization.The system can use fossil fuel thermal energy by two natural gas boilers(NGB) to assist in heating and making hot water.The heating energy efficiency was measured in the winter of 2010-2011.The coefficients of performance(COP) under different heating conditions are discussed.The performance of hot water production is tested in a local typical winter day and the solar thermal energy utilization factor is presented.The rusults show that the average system COP is 5.75 or 4.96 under different working conditions,and the typical solar energy utilization factor is 0.324. 展开更多
关键词 geothermal energy solar thermal energy district heating hot water supply
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Synergistic Influence of Pre-Harvest Calcium Sprays and Postharvest Hot Water Treatment on Fruit Firmness, Decay, Bitter Pit Incidence and Postharvest Quality of Royal Delicious Apples (<i>Malus x domestica</i>Borkh) 被引量:1
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作者 R. R. Sharma D. Singh R. K. Pal 《American Journal of Plant Sciences》 2013年第1期153-159,共7页
Experiments were conducted to observe the effect of pre-harvest calcium (Ca) applied as calcium chloride (1% W/V) and postharvest hot water treatment (HWT) on “Royal Delicious” apples. For this, apples were divided ... Experiments were conducted to observe the effect of pre-harvest calcium (Ca) applied as calcium chloride (1% W/V) and postharvest hot water treatment (HWT) on “Royal Delicious” apples. For this, apples were divided in 4 lots viz., untreated (neither Ca nor HWT), Ca alone (pre-harvest 3 sprays of CaCl2 (1.0% w/v) in the orchard), HWT (42℃ for 2 h). Apples of all four lots were stored in cold storage maintained at 0℃ ± 1℃ and 90% - 95% relative humidity for 6 months. After storage, fruits were removed to ambient conditions for 5 days, and then observations on decay area and incidence, bitter pit incidence, fruit Ca content, lipoxygenase (LOX) and antioxidant (AOX) activity, fruit firmness and fruit quality parameters were recorded. After 6 months in cold storage plus 5 day at 22℃ ± 2℃ and 70% + 4% RH, apples, which received Ca as pre-harvest spray or those which received postharvest hot water treatment or Ca + HWT had significantly lesser decay area (decay lesions) caused by Penicillium expansum or Botrytis cinerea than untreated ones (control). Ca + HWT treatment was significantly more effective on B. cinerea than P. expansum. Untreated apples exhibited higher incidence of bitter pit (18.2%) than those treated with Ca or HWT or both. Fruit Ca content (2.92% DM) were significantly lower and conversely the LOX activity (6.9 μmoles min–1×g–1FW) was higher in untreated apples. Similarly, total phenolics and AOX activity were also lower in the untreated apples than Ca or HWT treated. HWT or Ca treated apples have beneficial effects on fruit firmness, peel colour and quality parameters like TSS and ascorbic acid content. Thus, it is concluded that pre-harvest sprays of calcium chloride with postharvest HWT is highly useful for “Royal Delicious” for reducing decay loss, maintaining firmness, high levels of antioxidants and fruit quality. 展开更多
关键词 hot water Treatment LIPOXYGENASE ACTIVITY Antioxidant ACTIVITY BITTER Pit Fruit Quality
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The Hot Water Oil Expulsion Technique for Geothermal Resources 被引量:2
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作者 Xuezhong Wang 《Geomaterials》 2012年第2期42-48,共7页
With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric... With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric heating leads to considerable electrical consumption, low injection water temperature decreases reservoir temperature and increased crude oil viscosity. The prolonged temperature difference break up reservoir pore throat cement and framework minerals. To improve high-capacity channel communication, we proposed geothermal oil recovery. Broad-sense abundant geothermal resources and existing injection water technique equipment are used, deep-seated high temperature liquid (oil-gas-water mixture) draws geothermal warming flowing layer to transit heat upward, decreases viscidity and increases fluidity. Reservoir temperature different offer geothermal fountain. Practicability process is analyzed. statistics and reservoir temperature variation analysis of Gudong Oilfield, Shengli Oilfield Company, SINOPEC, we have designed flow-chart concept for geothermal oil recovery, suggested drilling multi-branch well in heavy oil reservoir as injection-well, at the same position of geothermal fountain well, using free-pressure pump to inject hot liquid directly to aimed oil layer, made oil recovery in surrounding wells. It is proposed that geothermal oil recovery forerunner test should be first conducted in favorable blocks. 展开更多
关键词 GEOTHERMAL Energy OIL RECOVERY hot water PROCESS Thermal PROCESS water Flood RECOVERY
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Contribution to the Study of Hot Water Scaling Phenomenon in the South of Touristic Area in Agadir City 被引量:1
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作者 M’barek Belattar Said Ben-Aazza +4 位作者 Rabeh Aba-Aaki Abdallah Hadfi Naima Hafid Larbi Boukbir Ali Driouiche 《Journal of Water Resource and Protection》 2016年第12期1035-1043,共10页
This work aims to study the phenomenon of scaling observed in the hot water pipelines in the southern seaside touristic installations of Agadir city. This phenomenon has led to the formation of solid deposits and adhe... This work aims to study the phenomenon of scaling observed in the hot water pipelines in the southern seaside touristic installations of Agadir city. This phenomenon has led to the formation of solid deposits and adherents to the internal walls of the facilities of the hot water. This deposit is at the origin of several technical, economic and environmental problems. It causes a decrease in the lifetime of boilers and a reduction of thermal exchanges and consequently a decrease in the energy efficiency of heating systems. In the present study, the samples of scale have been carried out at different points of hot water pipelines. The characterization of different scale samples recovered was conducted by X-ray fluorescence (XRF), elemental analysis (CHNS-O), infrared spectrometry (IR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Analytical results showed that scale samples collected on different sites in touristic hot water system are mostly formed by calcium carbonate. Thermodynamic conditions in the site were favourable to the aragonite variety formation. 展开更多
关键词 hot water Scaling Chemical Characterization Calcium Carbonate ARAGONITE Agadir City
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In Vitro Antioxidant Activity of Hot Water Extracts from 7 Different Sources of Ganoderma Lucidum 被引量:1
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作者 Jian NIE Shuilian YANG +1 位作者 Meihua MO Zhihao HU 《Medicinal Plant》 2017年第4期62-65,71,共5页
[Objectives] To study the in vitro antioxidant activity of hot water extracts from 7 different sources of Ganoderma lucidum mushroom.[Methods] The in vitro antioxidant activity of hot water extracts from 7 different s... [Objectives] To study the in vitro antioxidant activity of hot water extracts from 7 different sources of Ganoderma lucidum mushroom.[Methods] The in vitro antioxidant activity of hot water extracts from 7 different sources of G. lucidum was studied from total reducing capacity,scavenging of hydroxyl free radical( ·OH),superoxide anion( O_2^(2-)·),and DPPH free radical.[Results]Under the same concentration,hot water extracts wild G. lucidum in Maoer Mountain showed the strongest reducing capacity with the absorbency being 2. 48,the highest scavenging capacity of hydroxyl free radical( · OH) with the scavenging rate being 99. 46%,and the strongest scavenging ability of DPPH free radical with its scavenging rate being 96. 62%. The ability of scavenging superoxide anion free radical( O_2^(2-)·) ranked the third.[Conclusions]The hot water extracts from Maoer Mountain wild G. lucidum showed the highest antioxidant ability in three aspects,indicating that Maoer Mountain wild G. lucidum has high development potential. 展开更多
关键词 GANODERMA lucidum ANTIOXIDANT hot water EXTRACT
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Geochemical evaluation of low salinity hot water injection to enhance heavy oil recovery from carbonate reservoirs
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作者 Ji Ho Lee Kun Sang Lee 《Petroleum Science》 SCIE CAS CSCD 2019年第2期366-381,共16页
Although low salinity water injection(LSWI) has recovered residual oil after the conventional waterflood, highly viscous oil has remained in heavy oil reservoirs. Hot water injection is an economic and practical metho... Although low salinity water injection(LSWI) has recovered residual oil after the conventional waterflood, highly viscous oil has remained in heavy oil reservoirs. Hot water injection is an economic and practical method to improve oil mobility for viscous oil reservoirs. It potentially controls temperature-dependent geochemical reactions underlying the LSWI mechanism and oil viscosity. Therefore, this study has modeled and evaluated a hybrid process of low salinity hot water injection(hot LSWI) to quantify synergistic effects in heavy oil reservoirs. In comparison to seawater injection(SWI) and LSWI, hot LSWI results in more cation ion-exchange(Ca^(2+) and Mg^(2+)) and more wettability modification. Hot LSWI also reduces oil viscosity. In core-scaled systems, it increases oil recovery by 21% and 6% over SWI and LSWI. In a pilotscaled reservoir, it produces additional oil by 6% and 3% over SWI and LSWI. Probabilistic forecasting with uncertainty assessment further evaluates the feasibility of hot LSWI to consider uncertainty in the pilot-scaled reservoir and observes enhanced heavy oil production. This study confirms the viability of hot LSWI due to synergistic effects including enhanced wettability modification and oil viscosity reduction effects. 展开更多
关键词 Low SALINITY water INJECTION hot water INJECTION WETTABILITY modification GEOCHEMICAL reaction VISCOSITY reduction
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Changes in Soil Hot-Water Extractable C,N and P Fractions During Vegetative Restoration in Zhifanggou Watershed on the Loess Plateau 被引量:2
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作者 UE Sha LI Peng +2 位作者 LIU Guo-bin LI Zhan-bin ZHANG Chao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2250-2259,共10页
The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extr... The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extractable fractions could be used as indicators of soil quality change in Loess Plateau.The six vegetation types established in 1975 were(i) Robinia pseudoacacia L.,(ii) Caragana korshinkii Kom.,(iii) Pinus tabulaeformis Carr.,(iv) P.tabulaeformis-Amorpha fruticosa L.,(v) R.pseudoacacia-A.fruticosa,and(vi) grassland.A cropped hillslope plot and a Platycladus orientalis L.native forest plot were used as references.The results indicated that the conversion of native forest to cropland resulted in a significant decline in the hot-water extractable C,N and P fractions.Hot-water extractable C,N,and P increased when cultivated land was revegetated,but after 30 years the amount of hot-water extractable C,N,and P in revegetated fields was still much lower compared to native forest.Hot-water extractable fractions increased more under mixed-forest than under pure-forest stands.Furthermore,there was a significant correlation between the hot-water extractable fractions and soil chemical and microbiological properties.The results showed that hot-water extractable fractions could be used as indicators of soil quality change on the Loess Plateau. 展开更多
关键词 soil hot-water extractable fraction vegetative restoration Loess Plateau
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Effect of Hot Water Treatment on Postharvest Shelf Life and Quality of Broccoli
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作者 WU Ping and LI WuBeijing Vegetable Research Center, Beijing 100089 , P. R. China 《Agricultural Sciences in China》 CAS CSCD 2003年第4期469-472,共4页
Broccoli was stored at 0, 10, or 20℃after immersion in hot water (38 - 52℃) for 10 or 30 min. Yellowing of broccoli was significantly slowed and shelf life significantly increased when broccoli was treated with hot ... Broccoli was stored at 0, 10, or 20℃after immersion in hot water (38 - 52℃) for 10 or 30 min. Yellowing of broccoli was significantly slowed and shelf life significantly increased when broccoli was treated with hot water at 42 - 46℃and then stored at 10 or 20℃. Heat injury occurred when treatment was higher than 46℃in some varieties. Broccoli lasted 2-3 days longer when stored at 10℃ and 1-2 days longer when stored at 20℃ after hot water treatment at 46℃. There was no significant effect of treatment on shelf life after long time storage at 0℃. Weight loss was reduced by hot water treatment and the respiration behavior of the broccoli was also changed. 展开更多
关键词 BROCCOLI hot water treatment STORAGE RESPIRATION
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Mathematical Model of the Geothermal Water Resources in the South Hot Spring System in Chongqing
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作者 Liu Dongyan Luo Yunju Liu Xinrong 《Journal of China University of Geosciences》 SCIE CSCD 2005年第3期262-267,共6页
The geothermal waters of south hot spring, small hot spring and Qiaokouba in Chongqing, are all part of the south hot spring geothermal water system. Exploitation has caused a decline in the water levels of the south ... The geothermal waters of south hot spring, small hot spring and Qiaokouba in Chongqing, are all part of the south hot spring geothermal water system. Exploitation has caused a decline in the water levels of the south and small hot springs, which have not flowed naturally for 15 years. Now, bores pump geothermal water to the springs. If the water level drops below the elevation of the rivers, river-water will replenish the geothermal water, destroying this resource. It is therefore an urgent task to model the geothermal water system, to enable sustainable development and continued use of the geothermal water in Qiaokouba. A numerical simulation of the geothermal water system was adopted and a quantitative study on the planning scheme was carried out. A mathematical model was set up to simulate the whole geothermal water system, based on data from the research sites. The model determined the maximum sustainable water yield in Qiaokouba and the two hot springs, and the south hot spring and small hot spring sustainable yields are 1 100 m^3/d and 700 m^3/d from 2006 to 2010, 1 300 m^3/d and 1 000 m^3/d from 2011 to 2015, and 1 500 m^3/d and 1 200 m^3/d from 2016 to 2036. The maximum exploitable yield is 3 300 m^3/d from 2006 to 2036 in Qiaokouba. The model supplies a basis to adequately exploit and effectively protect the geothermal water resources, and to continue to develop the geothermal water as a tourist attraction in Chongqing. 展开更多
关键词 south hot spring geothermal water system geothermal water resources mathematical model sustainable development YIELD
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Nickel Chloride Promoted Glaser Coupling Reaction in Hot Water
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作者 PinHuaLI LeiWANG MinWANG JinCanYAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第11期1295-1298,共4页
A Glaser coupling reaction of terminal alkynes in the presence of nickel chloride without any organics and bases in hot water has been developed, which produces the corresponding homo-coupling products in good yields.
关键词 Glaser coupling reaction terminal alkynes nickel chloride hot water.
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Study on the effect of underground hot water on fracturing and earthquake activities
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作者 宋贯一 易立新 宋晓冰 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2000年第6期674-678,718,共6页
Utilizing the geological exploring information of Houhaoyao area and digital seismic network's data of Huailai area, the author studied the role of underground fluids (hot water) in the fracturing activities and i... Utilizing the geological exploring information of Houhaoyao area and digital seismic network's data of Huailai area, the author studied the role of underground fluids (hot water) in the fracturing activities and in the processes of seismogeny. The results show that the shear stress between two blocks of the fault is decreased rapidly and the vertical fault throw is obviously increased at the fracture segments where there is underground hot water action. With the vertical fault throw increasing, the shear stress transfers to two ends of the fault at the place where there is no underground hot water action, and the earthquake probably develops at these two ends of the fault. 展开更多
关键词 underground hot water tectonic activity seismogeny processP
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