期刊文献+
共找到2,016篇文章
< 1 2 101 >
每页显示 20 50 100
A Multimodal Critical Discourse Analysis of Lingnan Cultural Promotional Videos on Social Media
1
作者 Lu Jiang 《Journal of Contemporary Educational Research》 2024年第4期59-68,共10页
In recent years,more and more directors of culture and tourism have taken part in the promotion of local cultural tourism by cross-dressing,talent shows,and pushing their limits on self-media platforms.This study inve... In recent years,more and more directors of culture and tourism have taken part in the promotion of local cultural tourism by cross-dressing,talent shows,and pushing their limits on self-media platforms.This study investigates short videos of Lingnan culture promoted by directors general and deputy directors general of the Culture,Radio,Television,Tourism,and Sports Bureau of counties and cities in Guangdong Province on social media by the method of multimodal critical discourse analysis.The analysis of 33 videos shows that Lingnan culture is a domineering and confident culture,historical culture,graceful and elegant culture,and vibrant and active culture.Domineering and confident culture is embedded in the utterances and behaviors of the directors general or deputy directors general in the video.Historical culture is realized through the conversation with historical figures through time travel.Graceful and elegant culture is constructed in the depiction of sceneries and the depiction of characters’manners.Vibrant and active culture is represented in the depiction of the characters’actional process and analytical process. 展开更多
关键词 Lingnan culture Multimodal critical discourse analysis promotional videos TikTok WeChat
下载PDF
The Discourse-Historical Approach of Identity Construction in Corporate Promotional Videos for External Publicity Image
2
作者 Xiaodong Wang Jing Yu 《Proceedings of Business and Economic Studies》 2024年第2期178-183,共6页
Corporate identity construction of external publicity image is an important part of the development of enterprises.Based on Wodak’s discourse-historical approach,this study takes the text of COFCO’s English promotio... Corporate identity construction of external publicity image is an important part of the development of enterprises.Based on Wodak’s discourse-historical approach,this study takes the text of COFCO’s English promotional video as the research object,analyzes the corporate brand image,media image,organizational image,and environmental image constructed by the enterprises from three steps:linguistic expression,discourse strategy,and theme to provide references for Chinese enterprises to enhance their international influence. 展开更多
关键词 Corporate promotional videos External publicity image Discourse-historical approach
下载PDF
Interdiscursivity and Promotional Discourse:A Corpus-Assisted Genre Analysis of About Us Texts on Chinese University Websites 被引量:1
3
作者 Tao XIONG Qiuna LI 《Chinese Journal of Applied Linguistics》 2020年第4期397-416,525,共21页
The debate on the marketization of discourse in higher education has sparked and sustained interest among researchers in discourse and education studies across a diversity of contexts.While most research in this line ... The debate on the marketization of discourse in higher education has sparked and sustained interest among researchers in discourse and education studies across a diversity of contexts.While most research in this line has focused on marketized discourses such as advertisements,little attention has been paid to promotional discourse in public institutions such as the About us texts on Chinese university websites.The goal of the present study is twofold:first,to describe the generic features of the university About us texts in China;and second,to analyze how promotional discourse is interdiscursively incorporated in the discourse by referring to the broader sociopolitical context.Findings have indicated five main moves:giving an overview,stressing historical status,displaying strengths,pledging political and ideological allegiance,and communicating goals and visions.Move 3,displaying strengths,has the greatest amount of information and can be further divided into six sub-moves which presents information on campus facilities,faculty team,talent cultivation,disciplinary fields construction,academic research,and international exchange.The main linguistic and rhetorical strategies used in these moves are analyzed and discussed. 展开更多
关键词 About us text Chinese universities genre analysis INTERDISCURSIVITY MARKETIZATION promotional discourse
下载PDF
Dynamic Promotional Resource Allocation for Segment Specific and Spectrum Effect of Promotion for a Product Line Incorporating Repeat Purchase Behavior 被引量:1
4
作者 Prakash Chandra Jha Prerna Manik Anshu Gupta 《American Journal of Operations Research》 2013年第3期350-362,共13页
Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant... Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model. 展开更多
关键词 MARKET Segmentation DIFFERENTIATED MARKET PROMOTION Mass MARKET PROMOTION SPECTRUM EFFECT promotional Effort Allocation REPEAT Purchase Product Line Non Linear Programming Problem Differential Evolution
下载PDF
Retail Brand Building Through Promotional Communication: A Study That Focuses on Category Killers Promotional Flyers
5
作者 Roberto Manzano Anton Magdalena Ferran Aranaz Maria Puelles Gallo Miguel Llorens Marin 《Chinese Business Review》 2011年第3期217-225,共9页
Strong competition in retail distribution and the development of new purchasing options for the consumer generate a growing need to strengthen the retailers' brand image using all the communication elements, with pro... Strong competition in retail distribution and the development of new purchasing options for the consumer generate a growing need to strengthen the retailers' brand image using all the communication elements, with promotional flyers being one of the most important ways to do this. Promotional flyers make-up 5.1% of the money spent on communication and rank third place in terms of importance for retailers. The aim of this investigation work is to focus on analysing the utility of a promotional tool, such as a flyer, to fulfil a strategic objective, like creating a retail brand image, within a modern dynamic sector that is growing fast, such as Category Killers. Two sources of information have been used to carry out the research. On the One hand, a survey conducted on those responsible for the definition and execution of the promotional plan, and on the other hand, the accumulation and analysis of all the flyers issued into the market thought-out a year by those retailers which belong to this format, in order to conduct a study of seven defined image indicators. This information has been largely analyzed using multidimensional scaling method and chi-square test. As a result, we have managed to gather the differential elements in flyers execution between those retailers that prize the communications of image attributes and those retailers which concentrate on communicating price. The first group makes greater use of promotional theme related flyers, and shows greater differentiation in both product assortment and the depth of the range being communicated. 展开更多
关键词 retail image integrated communication store promotional flyers
下载PDF
Identity Construction and Image Identification: Evaluative Factors in Promotional Communication
6
作者 Maria Teresa Marins Freire Denise Wemeck 《Journalism and Mass Communication》 2013年第1期58-67,共10页
The paper addresses the identity construction in social organizations whose primary role is to define their singularity against other organizations and have them take on this singular role in the minds of its related ... The paper addresses the identity construction in social organizations whose primary role is to define their singularity against other organizations and have them take on this singular role in the minds of its related audiences. This construction is carried out in the course of the organizational existence and it is reflected in the image that it depicts. Those two elements are essential values to be handled by promotional communication through its several channels, means, and products. The aim of the study is to discuss the importance of corporate identity and image in the promotional communication of an organization. Bibliographical research and a case study were both used as methodologies. We have found the need to cultivate a positive image for the consolidation of the future of the organization including the contribution to the economic development of the country. 展开更多
关键词 social organization IDENTITY IMAGE VALUE promotional communication
下载PDF
Promotional Effect of Bismuth as Dopant in Bi-Doped Vanadyl Pyrophosphate Catalysts for Selective Oxidation of n-Butane to Maleic Anhydride 被引量:7
7
作者 Y.H.Taufiq-Yap Y.Kamiya K.P.Tan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第4期297-302,共6页
Bismuth-promoted (1% and 3%) vanadyl pyrophosphate catalysts were prepared by refluxing Bi(NO3)4.5H2O and VOPO4.2H2O in isobutanol. The incorporation of Bi into the catalysts lattice increased the surface area and... Bismuth-promoted (1% and 3%) vanadyl pyrophosphate catalysts were prepared by refluxing Bi(NO3)4.5H2O and VOPO4.2H2O in isobutanol. The incorporation of Bi into the catalysts lattice increased the surface area and lowered the overall V oxidation state. Profiles of temperature programmed reduction (TPR) in H2 show a significant shift of the maxima of major reduction peaks to lower temperatures for the Bi-promoted catalysts. A new peak was also observed at the low temperature region for the catalyst with 3% of Bi dopant. The addition of Bi also increased the total amount of oxygen removed from the catalysts. The reduction pattern and reactivity information provide fundamental insight into the catalytic properties of the catalysts. Bi-promoted catalysts were found to be highly active (71% and 81% conversion for 1% and 3% Bi promoted catalysts, respectively, at 703 K), as compared to the unpromoted material (47% conversion). The higher activity of the Bi-promoted catalysts is due to that these catalysts possess highly active and labile lattice oxygen. The better catalytic performance can also be attributed to the larger surface area. 展开更多
关键词 BISMUTH PROMOTER vanadyl pyrophosphate n-butane oxidation
下载PDF
Insight into the promotional mechanism of Cu modification towards wide-temperature NH3-SCR performance of NbCe catalyst 被引量:1
8
作者 Dongqi An Yuyao Yang +4 位作者 Weixin Zou Yandi Cai Qing Tong Jingfang Sun Lin Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期301-309,共9页
A simple strategy of Cu modification was proposed to broaden the operation temperature window for NbCe catalyst.The best catalyst Cu0.010/Nb1Ce3 presented over 90%NO conversion in a wide temperature range of 200-400℃... A simple strategy of Cu modification was proposed to broaden the operation temperature window for NbCe catalyst.The best catalyst Cu0.010/Nb1Ce3 presented over 90%NO conversion in a wide temperature range of 200-400℃and exhibited an excellent H_(2)O or/and SO_(2) resistance at 275℃.To understand the promotional mechanism of Cu modification,the correlation among the"activity-structure-property"were tried to establish systematically.Cu species highly dispersed on NbCe catalyst to serve as the active component.The strong interaction among Cu,Nb and Ce promoted the emergence of NbO4 and induced more Bronsted acid sites.And Cu modification obviously enhanced the redox behavior of the NbCe catalyst.Besides,EPR probed the Cu species exited in the form of monomeric and dimeric Cu^(2+),the isolated Cu^(2+)acted as catalytic active sites to promote the reaction:Cu^(2+)-NO_(3)^(-)+NO(g)→Cu^(2+)-NO_(2)^(-)+NO_(2)(g).Then the generated NO_(2) would accelerate the fast-SCR reaction process and thus facilitated the lowtemperature deNO_(x) efficiency.Moreover,surface nitrates became unstable and easy to decompose after Cu modification,thus providing additional adsorption and activation sites for NH3,and ensuring the improvement of catalytic activity at high temperature.Since the NH3-SCR reaction followed by E-R reaction pathway efficaciously over Cu_(0.010)/Nb_(1)Ce_(3) catalyst,the excellent H_(2)O and SO_(2) resistance was as expected. 展开更多
关键词 NH_(3)-SCR NbCe catalyst Cu modification NO_(2)promoting effect Fast-SCR Flue gas
下载PDF
Dual-targeting AAV9P1-mediated neuronal reprogramming in a mouse model of traumatic brain injury 被引量:1
9
作者 Jingzhou Liu Xin Xin +8 位作者 Jiejie Sun Yueyue Fan Xun Zhou Wei Gong Meiyan Yang Zhiping Li Yuli Wang Yang Yang Chunsheng Gao 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期629-635,共7页
Traumatic brain injury results in neuronal loss and glial scar formation.Replenishing neurons and eliminating the consequences of glial scar formation are essential for treating traumatic brain injury.Neuronal reprogr... Traumatic brain injury results in neuronal loss and glial scar formation.Replenishing neurons and eliminating the consequences of glial scar formation are essential for treating traumatic brain injury.Neuronal reprogramming is a promising strategy to convert glial scars to neural tissue.However,previous studies have reported inconsistent results.In this study,an AAV9P1 vector incorporating an astrocyte-targeting P1 peptide and glial fibrillary acidic protein promoter was used to achieve dual-targeting of astrocytes and the glial scar while minimizing off-target effects.The results demonstrate that AAV9P1 provides high selectivity of astrocytes and reactive astrocytes.Moreover,neuronal reprogramming was induced by downregulating the polypyrimidine tract-binding protein 1 gene via systemic administration of AAV9P1 in a mouse model of traumatic brain injury.In summary,this approach provides an improved gene delivery vehicle to study neuronal programming and evidence of its applications for traumatic brain injury. 展开更多
关键词 AAV9P1 ASTROCYTES astrocyte-to-neuron conversion GFAP promoter glial scar induced neurons neuronal reprogramming P1 peptide PTBP1 traumatic brain injury
下载PDF
Pricing and inventory decisions for non-instantaneous deteriorating items with price and promotional effort stochastic demand 被引量:3
10
作者 Hardik N.Soni Dipali N.Suthar 《Journal of Control and Decision》 EI 2019年第3期191-215,共25页
This study investigates an inventory model for a non-instantaneous deteriorating item with partial backlogging wherein the demand is stochastic in nature and depends on price and promotional effort whereas the deterio... This study investigates an inventory model for a non-instantaneous deteriorating item with partial backlogging wherein the demand is stochastic in nature and depends on price and promotional effort whereas the deterioration rate is time proportional.Under these settings,a mathematical model is developed with the objective to maximise the expected profit per unit time by determining the optimal price and the length of replenishment cycle.Some useful theoretical results are established to deduce the optimal replenishment schedule.An effective algorithmic procedure is developed to find the optimal solutions to the proposed model.The applicability of the proposed model is illustrated by numerical example.Sensitivity analysis of the optimal solution with respect to key parameters has been carried out and the implications are discussed.The study indicates that though promotional effort stimulates the market demand,it is beneficial in an economic sense when it applies in a conservative manner. 展开更多
关键词 INVENTORY non-instantaneous deterioration stochastic demand promotional effort partial backlogging
原文传递
Analysis and optimization of an EOQ inventory model with promotional efforts and back ordering under delay in payments 被引量:2
11
作者 R.Sundara Rajan R.Uthayakumar 《Journal of Management Analytics》 EI 2017年第2期159-181,共23页
In this paper,economic order quantity(EOQ)inventory model is considered subject to promotional efforts.We adopt a demand function which is dependent on sales teams’initiatives in which shortages are allowed which are... In this paper,economic order quantity(EOQ)inventory model is considered subject to promotional efforts.We adopt a demand function which is dependent on sales teams’initiatives in which shortages are allowed which are completely backlogged under the condition of permissible delay in payments with timedependent holding cost.The main objective of this paper is to determine the optimal replenishment schedule and optimal order quantity to maximize the total profit.Expressions for various optimal indices are provided.First,we prove that a unique optimal replenishment schedule exists.Second,we present an effective iterative algorithm to obtain the optimal solution.Furthermore,we establish some useful theorems to characterize the optimal solution to determine the values of replenishment schedule and optimal order quantity.Third,we prove that the total profit is a concave function via differential calculus and present numerical examples using SCILAB 5.5.0 to illustrate the model.Finally,we extend the numerical example by performing a sensitivity analysis of the model parameters and discuss managerial insights.This study suggests to the management of firms to determine the optimal order quantity,optimal inventory cycle length and sales teams’initiatives/promotional effort in order to achieve their maximum profits. 展开更多
关键词 promotional effort exponential holding cost BACKLOGGING permissible delay replenishment policy
原文传递
Promotional effect of silica on the combustion of nano-sized aluminum powder in carbon dioxide 被引量:1
12
作者 Baozhong ZHU Jinghui WANG +3 位作者 Qichang WANG Yunlan SUN Weiqi CHEN Jiquan WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第4期245-252,共8页
This paper presents how the combustion performance of nano-sized aluminum(nAl)powder in carbon dioxide are affected by silica. The ignition and combustion performance of nAl powder with silica addition were studied by... This paper presents how the combustion performance of nano-sized aluminum(nAl)powder in carbon dioxide are affected by silica. The ignition and combustion performance of nAl powder with silica addition were studied by a high-temperature tube furnace. An s-type thermocouple and a high-speed motion acquisition instrument were performed to evaluate the ignition temperature, maximum combustion temperature, maximum change of rate of temperature, and combustion propagation speed. The combustion efficiency and combustion products were measured and analyzed by a gas-volumetric method and an X-ray diffraction. The results show that silica added into nAl powder can enhance its maximum combustion temperature and maximum change of rate of temperature, while its ignition temperature increases slightly. The nAl powders with addition of 6.00 wt.% and 12.00 wt.% silica present high combustion propagation speeds, especially for the latter, it has high combustion efficiency. The effect mechanism of silica on the combustion of nAl powder in carbon dioxide was discussed. 展开更多
关键词 COMBUSTION MECHANISM Nano-sized aluminum powder promotional effect SILICA
原文传递
DNA G-Quadruplexes as Targets for Natural Product Drug Discovery
13
作者 Kai-Bo Wang Yingying Wang +1 位作者 Jonathan Dickerhoff Danzhou Yang 《Engineering》 SCIE EI CAS CSCD 2024年第7期39-51,共13页
DNA guanine(G)-quadruplexes(G4s)are unique secondary structures formed by two or more stacked Gtetrads in G-rich DNA sequences.These structures have been found to play a crucial role in highly transcribed genes,especi... DNA guanine(G)-quadruplexes(G4s)are unique secondary structures formed by two or more stacked Gtetrads in G-rich DNA sequences.These structures have been found to play a crucial role in highly transcribed genes,especially in cancer-related oncogenes,making them attractive targets for cancer therapeutics.Significantly,targeting oncogene promoter G4 structures has emerged as a promising strategy to address the challenge of undruggable and drug-resistant proteins,such as MYC,BCL2,KRAS,and EGFR.Natural products have long been an important source of drug discovery,particularly in the fields of cancer and infectious diseases.Noteworthy progress has recently been made in the discovery of naturally occurring DNA G4-targeting drugs.Numerous DNA G4s,such as MYC-G4,BCL2-G4,KRAS-G4,PDGFR-b-G4,VEGF-G4,and telomeric-G4,have been identified as potential targets of natural products,including berberine,telomestatin,quindoline,sanguinarine,isaindigotone,and many others.Herein,we summarize and evaluate recent advancements in natural and nature-derived DNA G4 binders,focusing on understanding the structural recognition of DNA G4s by small molecules derived from nature.We also discuss the challenges and opportunities associated with developing drugs that target DNA G4s. 展开更多
关键词 G-QUADRUPLEX Natural products ALKALOIDS CANCER PROMOTER
下载PDF
Measurement,associations,patterns,and promotion:Unveiling vital areas in physical activity epidemiology
14
作者 Kara M.Whitaker Guest editor Michael J.LaMonte 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期605-607,共3页
Physical activity(PA)epidemiology first emerged as a new field of study around the 1950s with publication of seminal investigations on London civil servants1 and has continued to evolve as a scientific discipline to p... Physical activity(PA)epidemiology first emerged as a new field of study around the 1950s with publication of seminal investigations on London civil servants1 and has continued to evolve as a scientific discipline to present time.This subdiscipline of epidemiology studies the frequencies,distributions,and dynamics of PA and its impact on human health,morbidity,and mortality.Research over the past 75 years has demonstrated numerous health benefits of PA.Based on these research findings,the World Health Organization recommends adults aged 18-64 years engage in at least 150-300 min of moderate-intensity aerobic PA per week,or at least 75-150 min of vigorous-intensity aerobic PA per week,or a combination of both intensities. 展开更多
关键词 EPIDEMIOLOGY PROMOTION continued
下载PDF
Pig H3K4me3,H3K27ac,and gene expression profiles reveal reproductive tissue-specific activity of transposable elements
15
作者 Tao Jiang Zhi-Min Zhou +6 位作者 Zi-Qi Ling Qing Zhang Zhong-Zi Wu Jia-Wen Yang Si-Yu Yang Bin Yang Lu-Sheng Huang 《Zoological Research》 SCIE CSCD 2024年第1期138-151,共14页
Regulatory sequences and transposable elements(TEs)account for a large proportion of the genomic sequences of species;however,their roles in gene transcription,especially tissue-specific expression,remain largely unkn... Regulatory sequences and transposable elements(TEs)account for a large proportion of the genomic sequences of species;however,their roles in gene transcription,especially tissue-specific expression,remain largely unknown.Pigs serve as an excellent animal model for studying genomic sequence biology due to the extensive diversity among their wild and domesticated populations.Here,we conducted an integrated analysis using H3K27ac ChIP-seq,H3K4me3 ChIP-seq,and RNA-seq data from 10 different tissues of seven fetuses and eight closely related adult pigs.We aimed to annotate the regulatory elements and TEs to elucidate their associations with histone modifications and mRNA expression across different tissues and developmental stages.Based on correlation analysis between mRNA expression and H3K27ac and H3K4me3 peak activity,results indicated that H3K27ac exhibited stronger associations with gene expression than H3K4me3.Furthermore,1.45%of TEs overlapped with either the H3K27ac or H3K4me3 peaks,with the majority displaying tissue-specific activity.Notably,a TE subfamily(LTR4C_SS),containing binding motifs for SIX1 and SIX4,showed specific enrichment in the H3K27ac peaks of the adult and fetal ovaries.RNA-seq analysis also revealed widespread expression of TEs in the exons or promoters of genes,including 4688 TE-containing transcripts with distinct development stage-specific and tissue-specific expression.Of note,1967 TE-containing transcripts were enriched in the testes.We identified a long terminal repeat(LTR),MLT1F1,acting as a testis-specific alternative promoter in SRPK2(a cell cycle-related protein kinase)in our pig dataset.This element was also conserved in humans and mice,suggesting either an ancient integration of TEs in genes specifically expressed in the testes or parallel evolutionary patterns.Collectively,our findings demonstrate that TEs are deeply embedded in the genome and exhibit important tissue-specific biological functions,particularly in the reproductive organs. 展开更多
关键词 Transposable elements PORCINE Histone modification Alternative promoter TE-containing transcript
下载PDF
Is it possible to run after positive affective experiences instead of health benefits without tackling social inequalities?
16
作者 Raphael H.O.Araujo Andre O.Werneck +1 位作者 Gilmar M.de Jesus Danilo R.P.Silva 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期756-758,共3页
We recently read the opinion piece titled“Why people should run after positive affective experiences instead of health benefits”,which was carried out by Maltagliati et al.^(1)and published in the Journal of Sport a... We recently read the opinion piece titled“Why people should run after positive affective experiences instead of health benefits”,which was carried out by Maltagliati et al.^(1)and published in the Journal of Sport and Health Science.The article started an important discussion about a physical activity(PA)promotion approach that encourages the use of affective experience to PA activity.Although we agree with the authors’point of view and believe that its message can generate an important insight for PA promotion,the authors presented a scenario where behavior change seems to be exclusively dependent on the individual.Recognizing the existence of other barriers to an active lifestyle(e.g.,social inequalities)could enhance the authors’suggested approach because many people live in conditions that reduce their opportunities to engage in affective experiences related to PA;furthermore,affective experiences can vary depending on individual context. 展开更多
关键词 PROMOTION INEQUALITIES furthermore
下载PDF
Understanding the catalytic performance and deactivation behaviour of second-promoter doped Pt/WO_(χ)/γ-Al_(2)O_(3) catalysts in the glycerol hydrogenolysis for selective and cleaner production of 1,3-propanediol
17
作者 Rafik Rajjak Shaikh Sittichai Damruang +2 位作者 Rais Ahmad Khan Supareak Praserthdam Piyasan Praserthdam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期486-507,共22页
The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the ca... The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the catalyst deactivation via sintering,metal leaching,and coking can predominantly occur in the aqueous phase reaction.In this work,the effect of reaction temperature,pressure and second promoter(Cu,Fe,Rh,Mn,Re,Ru,Ir,Sn,B,and P)on catalytic performance and deactivation behaviour of Pt/WOx/-Al2O3 was investigated.When doped with Rh,Mn,Re,Ru,Ir,B,and P,the second promoter boosts catalytic activity by promoting great dispersion of Pt on support and increasing Pt surface area.The increased Bronsted acid sites lead to selective synthesis of 1,3-PDO than 1,2-propanediol(1,2-PDO).The characterization studies of fresh and spent catalysts reveal that the main cause of catalyst deactivation is the Pt sintering,as interpreted based on XRD,CO chemisorption,and TEM analyses.The Pt sintering is affected depending on the second promoter that can either or reduce the interaction between Pt,WO_(χ)/γ and Al_(2)O_(3).As an electron acceptor of Pt in Pt/WO_(χ)/γ-Al_(2)O_(3),Re and Mn as second promoters resulted in increased Pt^(2+) on the catalytic surface,which strengthens the contact between Pt andγ-Al_(2)O_(3) and WO_(χ),resulting in a decrease in Pt sintering.The metal leaching and coking are not affected by the presence of second promoter.The catalyst modified with a second promoter possesses improved catalytic activity and 1,3-PDO production,however the stability continues to remain a challenge.The present work unrav-elled the determining parameters of catalytic activity and deactivation,thus providing a promising pro-tocol toward effective catalysts for glycerol hydrogenolysis. 展开更多
关键词 Glycerol hydrogenolysis 1 3-PROPANEDIOL Metal-support interaction Second promoter Liquid phase Catalyst deactivation
下载PDF
Enhanced extracellular production of alpha-lactalbumin from Bacillus subtilis through signal peptide and promoter screening
18
作者 Yuqi Zhu Pengdong Sun +6 位作者 Chunjian Li Yu Zhang Yu Wang Jingyuan Li Yanfeng Liu Jian Chen Yang Deng 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2310-2316,共7页
Alpha-lactalbumin(α-LA)is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants.In this study,Bacillus subtilis RIK1285 harboring AprE signal peptide(SP)was selec... Alpha-lactalbumin(α-LA)is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants.In this study,Bacillus subtilis RIK1285 harboring AprE signal peptide(SP)was selected as the original strain for the production ofα-LA.It was found thatα-LA was identified in the pellet after ultrasonic disruption and centrifugation instead of in the fermentation supernatant.The original strain most likely only producedα-LA intracellular,but not extracellular.To improve the expression and secretion ofα-LA in RIK1285,a library of 173 homologous SPs from the B.subtilis 168 genome was fused with target LALBA gene in the pBE-S vector and expressed extracellularly in RIK1285.SP YjcN was determined to be the best signal peptide.Bands in supernatant were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and purified by nickel column to calculate the highest yield signal peptide.In addition,different promoters(P_(aprE),P_(43),and P_(glv))were compared and applied.The results indicated that the strain RIK1285-pBE-P_(glv)-YjcN-LALBA had the highestα-LA yield,reaching 122.04μg/mL.This study demonstrates successful expression and secretion of humanα-LA in B.subtilis and establishes a foundation for simulating breast milk for infant formulas and developing bioengineered milk. 展开更多
关键词 Bacillus subtilis ALPHA-LACTALBUMIN Bioengineering milk Signal peptide Promoter screening
下载PDF
Revisiting the mitigation of coke formation:Synergism between support&promoters'role toward robust yield in the CO_(2)reformation of methane
19
作者 Zahra Taherian Vahid Shahed Gharahshiran +3 位作者 Xiaoxuan Wei Alireza Khataee Yeojoon Yoon Yasin Orooji 《Nano Materials Science》 EI CAS CSCD 2024年第5期536-547,共12页
CO_(2)reformation of methane(CRM)and CO_(2)methanation are two interconnected processes with significant implications for greenhouse gas reduction and sustainable energy production for industrial purposes.While Nibase... CO_(2)reformation of methane(CRM)and CO_(2)methanation are two interconnected processes with significant implications for greenhouse gas reduction and sustainable energy production for industrial purposes.While Nibased catalysis suffers from poor stability due to coke formation or sintering,we report a super stable remedy.The active sites of mesoporous MgO were loaded using wet impregnation.The incorporation of Ni and promoters altered the physical features of the catalysts.Sm–Ni/MgO showed the smallest crystallite size,specific surface area,and pore volume.The Sm–Ni/MgO catalyst was selected as the most suitable candidate for CRM,with 82%CH4 and H2/CO ratio of approximately 100%and also for CO_(2)methanation with the conversion of carbon dioxide(82%)and the selectivity toward methane reaches 100%at temperatures above 300ᵒC.Furthermore,the Sm–Ni/MgO catalyst was stable for 900 min of continuous reaction,without significant carbon deposition.This stability was largely due to the high oxygen mobility on the catalyst surface in the presence of Sm.Overall,we demonstrated the efficacy of using promoted Ni catalysts supported by mesoporous magnesia for the improved reformation of greenhouse gases. 展开更多
关键词 Mesoporous MgO Dry reforming CO_(2)methanation Oxygen vacancies PROMOTER
下载PDF
Development of biofertilizers for sustainable agriculture over four decades(1980-2022)
20
作者 Guangxu Zhao Xiaoling Zhu +8 位作者 Gang Zheng Guangfan Meng Ziliang Dong Ju Hye Baek Che Ok Jeon Yanlai Yao Yuan Hu Xuan Jie Zhang Baolei Jia 《Geography and Sustainability》 CSCD 2024年第1期19-28,共10页
The application of biofertilizers is becoming an inevitable trend to substitute chemical fertilizers for sustainable agriculture.To better understand the development of biofertilizers from 1980 to 2022,we used bibliom... The application of biofertilizers is becoming an inevitable trend to substitute chemical fertilizers for sustainable agriculture.To better understand the development of biofertilizers from 1980 to 2022,we used bibliometric mining to analyze 12,880 journal articles related to biofertilizer.The network cooccurrence analysis suggested that the biofertilizers research can be separated into three stages.The first stage(1980-2005)focused on nitrogen fixation.The second stage(2006-2015)concentrated on the mechanisms for increasing plant yield.The third stage(2016-2022)was the application of biofertilizers to improve the soil environment.The keyword analysis revealed the mechanisms of biofertilizers to improve plant-growth:biofertilizers can impact the nutritional status of plants,regulate plant hormones,and improve soil environments and the microbiome.The bacteria use as biofertilizers,included Pseudomonas,Azospirillum,and Bacillus,were also identified through bibliometric mining.These findings provide critical discernment to aid further study of biofertilizers for sustainable agriculture. 展开更多
关键词 BIOFERTILIZER Plant-growth-promoting bacteria Plant-growth promoting rhizobacteria BIBLIOMETRIC Research hotspots
下载PDF
上一页 1 2 101 下一页 到第
使用帮助 返回顶部