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A Decision Support System for Economic Development and Price Reform
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作者 Hu Lequn, Yang Shetang and Zhang WenzhongInstitute of System Science, Academia Sinica, Beijing, 100080Zhu JunNational Information Center of China, Beijing, 100072 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第1期65-73,共9页
In this paper, we present a real decision support system applied to China's macroeconomic management. The structure, design and functions of the system are discussed, and the problems occurring in designing and ma... In this paper, we present a real decision support system applied to China's macroeconomic management. The structure, design and functions of the system are discussed, and the problems occurring in designing and making the system are also studied. A case study for China's petroleum price reform is given at the end of the paper. 展开更多
关键词 Decision support system System analysis Interactive method Macroeconomic management price reform.
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How did the price and income elasticities of natural gas demand in China evolve from 1999 to 2015? The role of natural gas price reform 被引量:1
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作者 Kangyin Dong Xiucheng Dong Renjin Sun 《Petroleum Science》 SCIE CAS CSCD 2019年第3期685-700,共16页
As a cleaner,high-efficiency,and low-carbon fuel,natural gas has been an important fuel resource for China.To achieve a substantial increase in natural gas demand,China has sought to reform its natural gas pricing mec... As a cleaner,high-efficiency,and low-carbon fuel,natural gas has been an important fuel resource for China.To achieve a substantial increase in natural gas demand,China has sought to reform its natural gas pricing mechanism.Employing a set of unbalanced panel data for China’s 30 provinces covering 1999-2015,this study aims to estimate the evolving price and income elasticities of natural gas demand and explore the effect of natural gas price reform in China.For this purpose,a series of econometric techniques allowing for cross-sectional dependence and slope homogeneity is utilized.The results suggest that although natural gas demand in China still lacks negative price elasticity,the phenomenon is improving.Moreover,the estimates suggest that natural gas demand in China is indeed becoming increasingly sensitive to income changes.Our estimates also provide strong evidence in favor of the effect of natural gas price reform on the change in price elasticity as the price elasticity decreases in five of the seven regions.In addition,the results indicate large variations in the change in price and income elasticities of natural gas demand across China’s regions.Natural gas demand is becoming more price inelastic in Southwest China and Northwest China,while such demand in North China and East China responds less sensitively to income changes.These findings offer several policy suggestions for the reform of China’s natural gas market at the national and regional levels. 展开更多
关键词 Natural gas DEMAND price and INCOME ELASTICITIES price reform Regional analysis China
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Study on the Influencing Factors of Land Transfer Price in the Context of Rural Land Reform 被引量:2
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作者 Runzhi WANG 《Asian Agricultural Research》 2019年第8期20-22,共3页
Agricultural land is the key to large-scale agricultural management,and the transfer price is the key to the success or failure of land transfer. At present,there are many problems in the pricing of rural land transfe... Agricultural land is the key to large-scale agricultural management,and the transfer price is the key to the success or failure of land transfer. At present,there are many problems in the pricing of rural land transfer in China,such as low price,random pricing,and large price difference,which seriously hinder the development of rural land transfer. Drawing lessons from the research results of domestic and foreign scholars,combined with the actual situation of rural land transfer in China,this paper analyzes the influencing factors of land transfer price in the context of rural land reform. Finally,according to the influence of different factors on the behavior of agricultural land transfer,this paper proposes establishing and perfecting the evaluation system of contracted land,perfecting the evaluation institution of transferred land assets and establishing a unified dynamic monitoring system of land transfer price in the whole country,and then driving the broad masses of farmers to get rich together,which is of great significance to achieving the revitalization of China’s rural areas. 展开更多
关键词 RURAL LAND reform LAND TRANSFER price
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Energy Price Reform in China
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作者 Zhang Haixia Dong Xiucheng Zhao Xu 《Petroleum Science》 SCIE CAS CSCD 2006年第4期52-56,共5页
Market-based reform of energy prices is the most effective approach to enhancing energy efficiency. The policies of energy conservation and enhancing energy efficiency in the 11th Five-year Plan period (2006-2010) w... Market-based reform of energy prices is the most effective approach to enhancing energy efficiency. The policies of energy conservation and enhancing energy efficiency in the 11th Five-year Plan period (2006-2010) work directly to set up a series of reform measures related to energy pricing by market mechanism. Energy price reform will deeply influence China's industrial interest pattern, and its development in the next five years and even 10 or 20 years. This paper analyzes the significance, timing, present status and problems related to energy price reform, and discusses the goal, principle and measures of coal, electricity, oil and gas price reform separately. 展开更多
关键词 Energy price MARKETIZATION reform measure
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REFORM OF CRUDE OIL AND FINISHED OIL'S PRICE SYSTEM
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作者 Zhang Junshan(Sales Company of China National Petroleum Corporation) 《China Oil & Gas》 CAS 1998年第3期185-185,共1页
关键词 reform CRUDE OIL Finished OIL price POLICY
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An Analysis of China's Overall Price Level Movement and Macro-control since the Reform and Opening-up Period
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作者 王双正 李英 《China Economist》 2008年第2期81-94,共14页
This article begins with a detailed depiction of China's overall price movement since the reform and opening-up period, then proceeds with an in-depth analysis of the key factors affecting the overall price moveme... This article begins with a detailed depiction of China's overall price movement since the reform and opening-up period, then proceeds with an in-depth analysis of the key factors affecting the overall price movement. On this basis, the paper conducts a comparison of overall price plan/macro-control objectives and actual implementation results. Based on an in-depth dissection of the deviations between plan objectives and actual results, this article offers specific policy recommendations on how to improve and strengthen macro-control over overall price movement. 展开更多
关键词 Overall price level CONSUMER price price FLUCTUATION
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三色膏联合PRICE疗法治疗急性踝关节Ⅰ和Ⅱ度扭伤的临床效果
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作者 邱承玺 殷苏勤 +5 位作者 蔡晓辉 徐凯捷 牛锋 徐建德 詹红生 高慧 《中国当代医药》 CAS 2024年第27期85-88,共4页
目的探讨三色膏联合PRICE疗法治疗急性踝关节Ⅰ、Ⅱ度扭伤的临床效果。方法选取2022年2月至2023年5月上海市嘉定区中医医院骨伤科收治的52例Ⅰ、Ⅱ度急性踝关节扭伤患者作为研究对象,其中急诊患者35例,门诊患者17例,采用随机数字表法将... 目的探讨三色膏联合PRICE疗法治疗急性踝关节Ⅰ、Ⅱ度扭伤的临床效果。方法选取2022年2月至2023年5月上海市嘉定区中医医院骨伤科收治的52例Ⅰ、Ⅱ度急性踝关节扭伤患者作为研究对象,其中急诊患者35例,门诊患者17例,采用随机数字表法将其分为对照组和观察组,每组均失访1例,两组各25例纳入统计。对照组采用PRICE疗法治疗,观察组采用三色膏联合PRICE疗法,两组患者均治疗1周,治疗结束后,比较两组患者治疗前和治疗后第1、3周的视觉模拟评分法(VAS)评分及Mazur功能评分。结果52例患者中50例得到随访,随访时间不短于4周。治疗1、3周后,两组患者的VAS评分低于本组治疗前,Mazur功能评分高于本组治疗前,观察组的VAS评分低于对照组,Mazur功能评分高于对照组,差异有统计学意义(P<0.05)。结论三色膏联合PRICE疗法治疗急性踝关节Ⅰ、Ⅱ度扭伤可以获得更好的疗效,具有重要的临床价值和推广意义。 展开更多
关键词 三色膏 price疗法 踝关节 急性扭伤
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China-Price Guidelines Advance "Deep Reforms"
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作者 Se Yan Shuang Ding 《China's Foreign Trade》 2015年第6期18-21,共4页
·China commits to lifting price controls in competitive sectors by 2017 under new guidelines·Reforms focus on monopolistic sectors,public sector and heavily subsidised sectors·Price reforms send a stron... ·China commits to lifting price controls in competitive sectors by 2017 under new guidelines·Reforms focus on monopolistic sectors,public sector and heavily subsidised sectors·Price reforms send a strong signal of accelerating deep reformsMost remaining price controls to be lifted by 2017China recently announced a new round of pricing reforms and set a timetable for revamping the country’s pricing mechanism.Price controls for most goods and services in com- 展开更多
关键词 GOODS sector priceS REMAINING pricing competitive LIFTING electricity accelerating PLANNED
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Understanding the Relationship Between Shrinking Cities and Land Prices:Spatial Pattern,Effectiveness,and Policy Implications 被引量:1
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作者 WANG Xiaohui PENG Li +1 位作者 HUANG Kexin DENG Wei 《Chinese Geographical Science》 SCIE CSCD 2024年第1期1-18,共18页
Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(ex... Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas. 展开更多
关键词 shrinking cities land price propensity score matching(PSM) relative effectiveness China
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Goal and Progress of Power Tariff Reform——An interview with Liu Zhenqiu,Vice Director ofDepartment of Price,NDRC
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作者 Sha Yiqiang Journalist of China Power Enterprise Management Jia Yulu 《Electricity》 2008年第1期8-12,共5页
● Power tariffreform has made many important and substantialprogresses in respect ofmarketization● The benchmark tariff is a revolutionary progress made in China's power tariff reform● Coal-electricity price li... ● Power tariffreform has made many important and substantialprogresses in respect ofmarketization● The benchmark tariff is a revolutionary progress made in China's power tariff reform● Coal-electricity price linkage is a transitional approach which needs further improvement● The principle of T&D pricing is "cost plus profit," but it can also be based on pro rata control● China's electricity market should choose the mode of bilateral contracting combined withcentralized market● The direction of the power tariff reform is that electricity price shall be controlled mainly by the re-lationship between supply and demand in the 展开更多
关键词 Goal and Progress of Power Tariff reform An interview with Liu Zhenqiu Vice Director ofDepartment of price NDRC mode
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Brent vs.West Texas Intermediate in the US petro derivatives price formation
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作者 Alejandro Almeida Antonio A.Golpe +1 位作者 Juan Manuel Martín-Alvarez Jose Carlos Vides 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期729-739,共11页
In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over time.Considering the turbulent mo... In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over time.Considering the turbulent months of 2011,when Cushing Oklahoma had reached capacity and the crude oil export ban removal in 2015 as breakpoints,we apply this method both in the full sample and the three resultant regimes.First,results suggest our results show that both WTI and Brent display very similar behaviour with the refined products.Second,when attending to each regime,results derived from the first and third regimes are quite similar to the full sample results.Therefore,during the second regime,Brent crude oil became the benchmark in the petrol market,and it influenced the distillate products.Furthermore,our model can let us determine the price-setters and price-followers in the price formation mechanism through refined products.These results possess important considerations to policymakers and the market participants and the price formation. 展开更多
关键词 Crude oil prices Spatial panel model Refined products price formation
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Upcycling municipal solid waste to sustainable hydrogen via two-stage gasification-reforming
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作者 Hui Zhou Shuzhuang Sun +3 位作者 Yikai Xu Yeshui Zhang Shouliang Yi Chunfei Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期611-624,共14页
As global municipal solid waste(MSW)quantities continue to escalate,serious socio-environmental challenges arise,necessitating innovative solutions.Waste-to-hydrogen(WTH)via two-stage gasification-reforming(TSGR)prese... As global municipal solid waste(MSW)quantities continue to escalate,serious socio-environmental challenges arise,necessitating innovative solutions.Waste-to-hydrogen(WTH)via two-stage gasification-reforming(TSGR)presents an emergent technology for MSW upcycling,offering to ease waste management burdens and bolster the burgeoning hydrogen economy.Despite early initiatives to advance TSGR technology,a cohesive and critical analysis of cutting-edge knowledge and strategies to enhance hydrogen production remains lacking.This review aggregates literature on MSW upcycling to hydrogen via TSGR,with a focus on optimizing process control and catalytic efficiency.It underscores technological avenues to augment hydrogen output,curtail catalyst costs,and refine system performance.Particularly,the review illuminates the potential for integrating chemical and calcium looping into TSGR processes,identifying opportunities,and pinpointing challenges.The review concludes with a summary of the current state of techno-economic analysis for this technology,presenting outstanding challenges and future research directions,with the ultimate goal of transitioning WTH from theoretical to practical application. 展开更多
关键词 Municipal solidwaste Upcycling GASIFICATION reformING HYDROGEN
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Critical Makeover China advances medical reform to substantially lower drug prices
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作者 Hu Fan 《ChinAfrica》 2021年第4期30-31,共2页
On February 3,representatives of over 100 pharmaceutical companies gathered in a hotel in Shanghai.With documents in hand,they were there to attend a centralized procurement session organized by China’s health author... On February 3,representatives of over 100 pharmaceutical companies gathered in a hotel in Shanghai.With documents in hand,they were there to attend a centralized procurement session organized by China’s health authority. 展开更多
关键词 COMPANIES priceS ADVANCES
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Methanol steam reforming for hydrogen production driven by an atomically precise Cu catalyst
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作者 Weigang Hu Haoqi Liu +7 位作者 Yuankun Zhang Jiawei Ji Guangjun Li Xiao Cai Xu Liu Wen Wu Xu Weiping Ding Yan Zhu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1079-1084,共6页
Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can... Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can be used as light-harvesting materials in solar energy utilization such as photocatalytic methanol steam reforming.In this work,we report an atomically precise Cu_(13)cluster protected by dual ligands of thiolate and phosphine that can be viewed as the assembly of one top Cu atom and three Cu_(4)tetrahedra.The Cu_(13)H_(10)(SR)_(3)(PR’_(3))_(7)(SR=2,4-dichlorobenzenethiol,PR’_(3)=P(4-FC_(6)H_(4))_(3))cluster can give rise to highly efficient light-driven activity for methanol steam reforming toward H_(2)production. 展开更多
关键词 NANOCLUSTER PHOTOCATALYSIS Methanol steam reforming Atomically precise Copper catalyst
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Chemical looping reforming of the micromolecular component from biomass pyrolysis via Fe_(2)O_(3)@SBA-16
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作者 Yunchang Li Bo Zhang +3 位作者 Xiantan Yang Bolun Yang Shengyong Zhang Zhiqiang Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期120-134,共15页
To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling s... To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming. 展开更多
关键词 Biomass pyrolysis METHANE Chemical looping reforming Oxygen carrier Kinetic analysis
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Research on the Reform of the Process-Tracking Ideological and Political Assessment System in Applied Universities:Taking the Personal Finance Course as an Example 被引量:1
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作者 Jing Chen 《Journal of Contemporary Educational Research》 2024年第1期179-185,共7页
Using the Xi’an Mingde Institute of Technology students as the teaching object and the Personal Finance course as an example,we explore the reform of the ideological and political assessment system of process-trackin... Using the Xi’an Mingde Institute of Technology students as the teaching object and the Personal Finance course as an example,we explore the reform of the ideological and political assessment system of process-tracking courses in applied universities.The article analyzes the feasibility of applying the curriculum ideological and political assessment system in college courses and compares the traditional assessment system.It also proposes that applying curriculum ideological and political assessment to the college curriculum assessment system will help improve students’understanding of the“value guidance”in curriculum ideological and political education and enhance the teaching effect. 展开更多
关键词 Curriculum ideological and political education Teaching reform Curriculum assessment
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Optimizing the sulfur-resistance and activity of perovskite oxygen carrier for chemical looping dry reforming of methane
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作者 Yuelun Li Dong Tian +6 位作者 Lei jiang Huicong Zuo LiNan Huang Mingyi Chen Jianchun Zuo Hua Wang Kongzhai Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期259-271,共13页
Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modu... Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance. 展开更多
关键词 Perovskite oxygen carriers Chemical looping reforming Sulfur-resistance Dual substitution SYNGAS
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Economic Resilience in Bangladesh: Analyzing Household Well-Being amidst Price Hikes through ANOVA and Paired Sample t-Test Insights
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作者 Esita Ghosh 《Open Journal of Statistics》 2024年第1期55-89,共35页
This study delves into the multifaceted impact of price hikes on the standard of living in Bangladesh, with a specific focus on distinct socioeconomic segments. Amidst Bangladesh’s economic growth, the challenges of ... This study delves into the multifaceted impact of price hikes on the standard of living in Bangladesh, with a specific focus on distinct socioeconomic segments. Amidst Bangladesh’s economic growth, the challenges of rising inflation and increased living costs have become pressing concerns. Employing a mixed-methods approach combines quantitative data from a structured survey with qualitative insights from in-depth interviews and focused group discussions to analyze the repercussions of price hikes. Stratified random sampling ensures representation across affluent, middle-class, and economically disadvantaged groups. Utilizing data [1] from 2020 to November 2023 on the yearly change in retail prices of essential commodities, analysis reveals significant demographic shifts, occupational changes, and altered asset ownership patterns among households. The vulnerable population, including daily wage laborers and low-income individuals, is disproportionately affected by adjustments in consumption, income generation, and living arrangements. Statistical analyses, including One-Way ANOVA and Paired Sample t-tests, illuminate significant mean differences in strategies employed during price hikes. Despite challenges, the prioritization of education remains evident, emphasizing its resilience in the face of economic hardships. The result shows that price hikes, especially in essential items, lead to substantial adjustments in living costs, with items like onions, garlic, and ginger experiencing significant increases of 275%, 108%, and 483%, respectively. 展开更多
关键词 price Hike Economic Growth SOCIOECONOMIC Development Households
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Using Aspen HYSYS to Develop a Custom Molecule-based Reformer Model
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作者 Wang Xinlei Hou Zhen +3 位作者 Zhou Xiang Zhang Lei Liu Xiaoyu Guo Jinbiao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期102-108,共7页
A new continuous catalytic reforming model was configured by using a molecule-based reactor module. Themodel was based on the Sinopec Research Institute of Petroleum Processing Co., Ltd. continuous catalytic reformer ... A new continuous catalytic reforming model was configured by using a molecule-based reactor module. Themodel was based on the Sinopec Research Institute of Petroleum Processing Co., Ltd. continuous catalytic reformer fullmodel, and was reduced to a size of 157 naphtha molecules (C1−C12) that underwent 764 reactions. The new model inheritedthe advantages of the original model, and had better solving performance and flexibility owing to support by the AspenHYSYS environment. Typical commercial plant data were selected for model validation, which showed advantages in theaccuracy of detailed predictions and the range of its application. In addition, the solving time was reduced from minutes toseconds. Therefore, the simplified model proved to be feasible for industrial application. 展开更多
关键词 molecular-based model continuous catalytic reformer Aspen HYSYS
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Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect
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作者 HOU Ming-xiao HUANG Bing-xiang +2 位作者 ZHAO Xing-long JIAO Xue-jie ZHENG Chen-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2446-2466,共21页
Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way t... Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way to control the hard limestone roof.In this study,the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed.The results show that the acid with stronger hydrogen production capacity after ionization(pK_(a)<0)has more prominent damage to the mineral grains of limestone.When pKa increases from−8.00 to 15.70,uniaxial compressive strength and elastic modulus of limestone increase by 117.22%and 75.98%.The influence of acid concentration is manifested in the dissolution behavior of mineral crystals,the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength,and the strength after 15%concentration reformation can be reduced by 59.42%.The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage(within 60 min).The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system.Based on the analytic hierarchy process method,the influence weights of acid type,acid concentration and acidification time on strength are 24.30%,59.54% and 16.16%,respectively.The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines. 展开更多
关键词 hard roof acidic effect structural reformation strength weakening influencing factors
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