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理想的反应器 Alfa Laval公司开发高能效的新型平板式反应器
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《流程工业》 2008年第1期54-55,共2页
化工行业是欧洲第三大制造业,充满了竞争压力和相关的环境立法规定,目的在于不断督察工厂的制造及加工技术。寻找更安全、更清洁、更节能的制造工艺,成为行业内首要关注的问题和不断提升的挑战。
关键词 反应器 ALFA 平板式 理想 能效 开发 化工行业 加工技术
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A novel approach to the dynamic response analysis of Euler-Bernoulli beams resting on a Winkler soil model and subjected to impact loads
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作者 Adolfo Foriero Filippo Santucci de Magistris Giovanni Fabbrocino 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期389-401,共13页
This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact loading.The approach considers that damping has much less impor... This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact loading.The approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the system.The development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are presented.This study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably affected.In particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification factor.The computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem. 展开更多
关键词 beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor
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Modelling of the variation of granular base materials resilient modulus with material characteristics and humidity conditions
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作者 Jean-Pascal Bilodeau Erdrick Leandro Perez-Gonzalez Ali Saeidi 《Journal of Road Engineering》 2024年第1期27-35,共9页
This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines... This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water content.The results showed that the percentage of fractured coarse aggregates particles(FR)has a more significant impact on the resilient modulus(Er)of crushed granular materials used in pavement construction than the combined indicator of the fines content and sample volumetrics(nf).Crushed granular materials with a higher percentage of fractured coarse aggregates are relatively insensitive to changes in the degree of saturation,but become more sensitive as the fine fraction porosity decreases.An adjusted model was proposed based on the existing formulation,but considers a complex parameter to describe and adjust the sensitivity of base granular materials to variations in moisture content with respect to fabrication charac-teristics,fines content and volumetric properties.The model shows that the variation of Er values is below10%for fully crushed granular materials.However,it reaches approximately±12%for materials with 75%of crushed coarse aggregates andþ40%and-25%for materials with FR=50%.This model could help select good ag-gregates characteristics and adjust grain-size distribution for environments where significant moisture content variations can occur in the pavement system,such as in the Province of Quebec(Canada).As it is based on pa-rameters that can be easily determined or estimated,it also represents a valuable tool for detailed design and analysis that can consider material characteristics. 展开更多
关键词 Resilient modulus Degree of saturation Humidity conditions Unbound granular materials Pavement base
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Metamorphoses of the University and the Pathways of Indigenous Students in Quebec:Issues of Accessibility to Studies and Academic Persistence from a Perspective of the Decolonization of Education-A Secondary Publication
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作者 Jean-Luc Ratel Annie Pilote 《Journal of Contemporary Educational Research》 2024年第4期304-315,共12页
In connection with the historical context of social segregation and the assimilative aim of formal education imposed on them,the Indigenous Peoples of Québec have long been excluded from higher education.Today,ev... In connection with the historical context of social segregation and the assimilative aim of formal education imposed on them,the Indigenous Peoples of Québec have long been excluded from higher education.Today,even if their graduation rates are increasing,a persistent gap with the non-Indigenous population is maintained.The data in this article are drawn from 23 interviews with students and university graduates of the First Nations of Québec,as part of a thesis in educational sciences.Our paper analyzes how these students manage to combine the contributions of Indigenous education with those of Western education by developing paths that are part of the decolonization movement of education.Their relationship to Indigenous identity and cultures clearly influences their educational background and is analyzed taking into account power relations with the dominant culture.Our paper emphasizes more particularly the relationship to studies,the adaptation to the student profession,and the balance between studies,work,and family among Indigenous students,in a context of transition from university to multiversity which contributed to the increase of Indigenous university attendance. 展开更多
关键词 Educational inclusion and exclusion Higher and university education Educational inequalities Canada
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Lightning in a Forest (Wild) Fire: Mechanism at the Molecular Level
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作者 See Leang Chin Xueliang Guo +4 位作者 Harmut Schroeder Huanbin Xu Tie-Jun Wang Ruxin Li Weiwei Liu 《Atmospheric and Climate Sciences》 2024年第1期128-135,共8页
The mechanism of lightning that ignites a forest fire and the lightning that occurs above a forest fire are explained at the molecular level. It is based on two phenomena, namely, internal charge separation inside the... The mechanism of lightning that ignites a forest fire and the lightning that occurs above a forest fire are explained at the molecular level. It is based on two phenomena, namely, internal charge separation inside the atmospheric cloud particles and the existence of a layer of positively charged hydrogen atoms sticking out of the surface of the liquid layer of water on the surface of rimers. Strong turbulence-driven collisions of the ice particles and water droplets with the rimers give rise to breakups of the ice particles and water droplets into positively and negatively charged fragments leading to charge separation. Hot weather in a forest contributes to the updraft of hot and humid air, which follows the same physical/chemical processes of normal lightning proposed and explained recently[1]. Lightning would have a high probability of lighting up and burning the dry biological materials in the ground of the forest, leading to a forest (wild) fire. The burning of trees and other plants would release a lot of heat and moisture together with a lot of smoke particles (aerosols) becoming a strong updraft. The condition for creating lightning is again satisfied which would result in further lightning high above the forest wild fire. 展开更多
关键词 Forest Wild Fire LIGHTNING Molecular Level
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Towards Mutuality in the Canada-China Relationship:The Experience of the Department of Surgery at Laval University since the 1980s
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作者 Robert GUIDOIN WANG Lu Yvan DOUVILLE 《Frontiers of Education in China》 2015年第3期384-400,共17页
The Department of Surgery at Laval University has been a key player in the development of Canada-China cooperation since the 1980s.The projects initiated and developed by Jean Couture and Guojin Liu to address cancer ... The Department of Surgery at Laval University has been a key player in the development of Canada-China cooperation since the 1980s.The projects initiated and developed by Jean Couture and Guojin Liu to address cancer issues,and specifically breast cancer,were heralded as outstanding successes.In the meantime,the Department of Surgery at Laval University trained numerous Chinese scholars,students,and post-doctoral fellows who became leaders in their fields of expertise.A few of these scholars and students settled in Canada,but the vast majority returned home.Since 2007,a highly specialized research program related to surgical implants with the College of Textiles at Donghua University has been opening new avenues in medical textiles to develop expertise through student training,to launch bridges between textile engineers and clinicians,and to provide the industry with a unique expertise.The final goal is to improve the accessibility and affordability of health care delivery in both Canada and China.China is now a key player in related research and no longer requires foreign assistance.Since it can easily find multiple partners,Canada must be alert to building on its legacy and maintaining its privileged position.China is now a place for Canadian champions. 展开更多
关键词 Canada-China cooperation MUTUALITY Changchun Laval University Donghua University
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A New Method for Diagnosis of Leukemia Utilizing a Hybrid DL-ML Approach for Binary and Multi-Class Classification on a Limited-Sized Database
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作者 Nilkanth Mukund Deshpande Shilpa Gite +2 位作者 Biswajeet Pradhan Abdullah Alamri Chang-Wook Lee 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期593-631,共39页
Infection of leukemia in humans causes many complications in its later stages.It impairs bone marrow’s ability to produce blood.Morphological diagnosis of human blood cells is a well-known and well-proven technique f... Infection of leukemia in humans causes many complications in its later stages.It impairs bone marrow’s ability to produce blood.Morphological diagnosis of human blood cells is a well-known and well-proven technique for diagnosis in this case.The binary classification is employed to distinguish between normal and leukemiainfected cells.In addition,various subtypes of leukemia require different treatments.These sub-classes must also be detected to obtain an accurate diagnosis of the type of leukemia.This entails using multi-class classification to determine the leukemia subtype.This is usually done using a microscopic examination of these blood cells.Due to the requirement of a trained pathologist,the decision process is critical,which leads to the development of an automated software framework for diagnosis.Researchers utilized state-of-the-art machine learning approaches,such as Support Vector Machine(SVM),Random Forest(RF),Na飗e Bayes,K-Nearest Neighbor(KNN),and others,to provide limited accuracies of classification.More advanced deep-learning methods are also utilized.Due to constrained dataset sizes,these approaches result in over-fitting,reducing their outstanding performances.This study introduces a deep learning-machine learning combined approach for leukemia diagnosis.It uses deep transfer learning frameworks to extract and classify features using state-of-the-artmachine learning classifiers.The transfer learning frameworks such as VGGNet,Xception,InceptionResV2,Densenet,and ResNet are employed as feature extractors.The extracted features are given to RF and XGBoost classifiers for the binary and multi-class classification of leukemia cells.For the experimentation,a very popular ALL-IDB dataset is used,approaching a maximum accuracy of 100%.A private real images dataset with three subclasses of leukemia images,including Acute Myloid Leukemia(AML),Chronic Lymphocytic Leukemia(CLL),and Chronic Myloid Leukemia(CML),is also employed to generalize the system.This dataset achieves an impressive multi-class classification accuracy of 97.08%.The proposed approach is robust and generalized by a standardized dataset and the real image dataset with a limited sample size(520 images).Hence,this method can be explored further for leukemia diagnosis having a limited number of dataset samples. 展开更多
关键词 Leukemia diagnosis deep learning machine learning random forest XGBoost
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基于光学偏振成像的镜面反射分量分离算法 被引量:1
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作者 景元萍 彭群聂 税昌健 《电光与控制》 CSCD 北大核心 2023年第2期36-40,共5页
成像过程中目标表面常存在大区域耀光、光斑等镜面反射光的干扰,直接限制识别、匹配等视觉性能。提出一种基于光学偏振成像的镜面反射分量分离算法,抑制目标表面镜面反射的影响。结合双色反射模型的偏振成像机理分析,利用体反射与镜面... 成像过程中目标表面常存在大区域耀光、光斑等镜面反射光的干扰,直接限制识别、匹配等视觉性能。提出一种基于光学偏振成像的镜面反射分量分离算法,抑制目标表面镜面反射的影响。结合双色反射模型的偏振成像机理分析,利用体反射与镜面反射的起偏特性差异,提出了基于Stokes参数的体反射强度反演机制;构建CbCr空间双色度矢量约束,实现CbCr空间下镜面反射分量的物理隔离;同时联合遍历式最小二乘法进行反射系数的快速求解,高效引导镜面反射分量分离,恢复目标表面原有细节信息。实验结果表明,所提算法能准确抑制分离镜面反射分量,极大保留目标原有色彩、结构、纹理特征,场景适应性强,目标还原度高。 展开更多
关键词 镜面反射分量 偏振成像 CbCr空间双色度矢量 遍历式最小二乘法
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Methylome and transcriptome data integration reveals potential roles of DNA methylation and candidate biomarkers of cow Streptococcus uberis subclinical mastitis 被引量:2
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作者 Mengqi Wang Nathalie Bissonnette +6 位作者 Mario Laterriere Pier‑Luc Dudemaine David Gagne Jean‑Philippe Roy Xin Zhao Marc‑Andre Sirard Eveline M.Ibeagha‑Awemu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期593-613,共21页
Background:Mastitis caused by different pathogens including Streptococcus uberis(S.uberis)is responsible for huge economic losses to the dairy industry.In order to investigate the potential genetic and epigenetic regu... Background:Mastitis caused by different pathogens including Streptococcus uberis(S.uberis)is responsible for huge economic losses to the dairy industry.In order to investigate the potential genetic and epigenetic regulatory mecha‑nisms of subclinical mastitis due to S.uberis,the DNA methylome(whole genome DNA methylation sequencing)and transcriptome(RNA sequencing)of milk somatic cells from cows with naturally occurring S.uberis subclinical mastitis and healthy control cows(n=3/group)were studied.Results:Globally,the DNA methylation levels of CpG sites were low in the promoters and first exons but high in inner exons and introns.The DNA methylation levels at the promoter,first exon and first intron regions were nega‑tively correlated with the expression level of genes at a whole‑genome‑wide scale.In general,DNA methylation level was lower in S.uberis‑positive group(SUG)than in the control group(CTG).A total of 174,342 differentially methylated cytosines(DMCs)(FDR<0.05)were identified between SUG and CTG,including 132,237,7412 and 34,693 DMCs in the context of CpG,CHG and CHH(H=A or T or C),respectively.Besides,101,612 methylation haplotype blocks(MHBs)were identified,including 451 MHBs that were significantly different(dMHB)between the two groups.A total of 2130 differentially expressed(DE)genes(1378 with up‑regulated and 752 with down‑regulated expression)were found in SUG.Integration of methylome and transcriptome data with MethGET program revealed 1623 genes with signifi‑cant changes in their methylation levels and/or gene expression changes(MetGDE genes,MethGET P‑value<0.001).Functional enrichment of genes harboring≥15 DMCs,DE genes and MetGDE genes suggest significant involvement of DNA methylation changes in the regulation of the host immune response to S.uberis infection,especially cytokine activities.Furthermore,discriminant correlation analysis with DIABLO method identified 26 candidate biomarkers,including 6 DE genes,15 CpG‑DMCs and 5 dMHBs that discriminated between SUG and CTG.Conclusion:The integration of methylome and transcriptome of milk somatic cells suggests the possible involve‑ment of DNA methylation changes in the regulation of the host immune response to subclinical mastitis due to S.uberis.The presented genetic and epigenetic biomarkers could contribute to the design of management strategies of subclinical mastitis and breeding for mastitis resistance. 展开更多
关键词 Discriminant biomarkers Gene expression Genome‑wide DNA methylation pattern Immune processes and pathways Methylation haplotype block Milk somatic cell Streptococcus uberis Subclinical mastitis
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Improvement strategies for Ni-based alcohol steam reforming catalysts
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作者 Alex Desgagnés Ommolbanin Alizadeh Sahraei Maria C.Iliuta 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期447-479,I0010,共34页
Steam reforming(SR)of fossil methane is already a well-known,documented and established expertise in the industrial sector as it accounts for the vast majority of global hydrogen production.From a sustainable developm... Steam reforming(SR)of fossil methane is already a well-known,documented and established expertise in the industrial sector as it accounts for the vast majority of global hydrogen production.From a sustainable development perspective,hydrogen production by SR of biomass-derived feedstock represents a promising alternative that could help to lower the carbon footprint of the traditional process.In this regard,bio-alcohols such as methanol,ethanol or glycerol are among the attractive candidates that could serve as green hydrogen carriers as they decompose at relatively low temperatures in the presence of water compared to methane,allowing for improved H_(2)yields.However,significant challenges remain regarding the activity and stability of nickel-based catalysts,which are most widely used in alcohol SR processes due to their affordability and ability to break C–C,O–H and C–H bonds,yet are prone to rapid deactivation primarily caused by coke deposition and metal particle sintering.In this state-of-the-art review,a portfolio of strategies to improve the performance of Ni-based catalysts used in alcohol SR processes is unfolded with the intent of pinpointing the critical issues in catalyst development.Close examination of the literature reveals that the efforts tackling these recurring issues can be directed at the active metal,either by tuning Ni dispersion and Ni-support interactions or by targeting synergistic effects in bimetallic systems,while others focus on the support,either by modifying acid-base character,oxygen mobility,or by embedding Ni in specific crystallographic structures.This review provides a very useful tool to orient future work in catalyst development. 展开更多
关键词 H2 production Alcohol steam reforming Ni-based catalysts Catalyst development SINTERING Coke formation
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A Novel Stackelberg-Game-Based Energy Storage Sharing Scheme Under Demand Charge
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作者 Bingyun Li Qinmin Yang Innocent Kamwa 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期462-473,共12页
Demand response(DR)using shared energy storage systems(ESSs)is an appealing method to save electricity bills for users under demand charge and time-of-use(TOU)price.A novel Stackelberg-game-based ESS sharing scheme is... Demand response(DR)using shared energy storage systems(ESSs)is an appealing method to save electricity bills for users under demand charge and time-of-use(TOU)price.A novel Stackelberg-game-based ESS sharing scheme is proposed and analyzed in this study.In this scheme,the interactions between selfish users and an operator are characterized as a Stackelberg game.Operator holds a large-scale ESS that is shared among users in the form of energy transactions.It sells energy to users and sets the selling price first.It maximizes its profit through optimal pricing and ESS dispatching.Users purchase some energy from operator for the reduction of their demand charges after operator's selling price is announced.This game-theoretic ESS sharing scheme is characterized and analyzed by formulating and solving a bi-level optimization model.The upper-level optimization maximizes operator's profit and the lower-level optimization minimizes users'costs.The bi-level model is transformed and linearized into a mixed-integer linear programming(MILP)model using the mathematical programming with equilibrium constraints(MPEC)method and model linearizing techniques.Case studies with actual data are carried out to explore the economic performances of the proposed ESS sharing scheme. 展开更多
关键词 Bi-level optimization demand charge energy storage system(ESS)sharing energy transaction mathematical program with equilibrium constraints(MPEC) stackelberg game
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Parkia biglobosa (Jacq.) R. Br. Ex G. Don Fruit Pulp Supplementation in the Diet of Local Chickens in Burkina Faso: Effects on Growth Performance and Carcass Characteristics
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作者 Hadidjatou Bélem Roland Nâg-Tiero Meda +8 位作者 Benjamin Kouliga Koama Windmi Kagambéga Sandrine Nadege Da Anne Flora Drabo Assetou Sawadogo Cyprial Ndumiso Ncobela Marie-Pierre Létourneau-Montminy Amadou Traoré George Anicet Ouédraogo 《Food and Nutrition Sciences》 2023年第11期1119-1132,共14页
This work aimed to evaluate the effects of supplementation of Parkia biglobosa fruit pulp flour in the CPAVI chicken ration on the growth performance and carcass characteristics of local chickens. This study involved ... This work aimed to evaluate the effects of supplementation of Parkia biglobosa fruit pulp flour in the CPAVI chicken ration on the growth performance and carcass characteristics of local chickens. This study involved 50 local chicks of eight weeks of age. Chickens were divided into 5 groups of 10 chicks corresponding to five experimental rations containing 0%, 1%, 2%, 3% and 4% pulp from fruits of P. biglobosa. The nutritional composition of P. biglobosa fruit pulps were analyzed, then growth parameters and carcass characteristics were measured. The results showed that the fruit pulps of P. biglobosa were rich in metabolizable energy (4015.02 ± 0.21 Kcal/kg), crude fiber (16.88% ADF and 19.81% NDF) and potassium (2.45% ± 0.01%). Thus, the group of local chickens fed the diet containing 1% supplementation had a significantly higher live weight (1200.85 g) and carcass yield (91.99 g) (P supplementation. Additionally, individual feed consumption and average daily gain of the group at 1% supplementation were higher. In short, the flour from the pulp of the fruit of Parkia biglobosa can be supplemented up to 1% in the CPAVI pullet type feed for local chickens. 展开更多
关键词 Local Chicken Parkia biglobosa CPAVI Growth Performance Burkina Faso
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Optimization of Photo-Fenton Catalyst Preparation Based Bamboo Carbon Fiber by Response Surface Methodology
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作者 Yizhang Wang Zhaoyang Yu +5 位作者 Jinbo Hu Shanshan Chang Yuan Liu Ting Li Gonggang Liu Xiaodong(Alice)Wang 《Journal of Renewable Materials》 SCIE EI 2023年第1期147-165,共19页
In this paper,the residue from bamboo factory has been used to design photo-Fenton catalyst,which has the advantages of low cost and magnetic recycling.The photo-Fenton catalytic performance of the biocarbon-based cat... In this paper,the residue from bamboo factory has been used to design photo-Fenton catalyst,which has the advantages of low cost and magnetic recycling.The photo-Fenton catalytic performance of the biocarbon-based catalyst was excellent and its optimal preparation process was also explored by response surface methodology.First,bamboo-carbon fiber was selected as the photo-Fenton catalyst carrier.Subsequently,the surface of the car-bon fiber was modified,with which dopamine,nano-Fe_(3)O_(4) and nano-TiO_(2) were successively loaded by hydro-thermal method.After the single factor tests,four factors including dopamine concentration,ferric chloride mass,P25 titanium dioxide mass and liquid-solid ratio were selected as the characteristic values.The degradation efficiency of photo-Fenton catalyst to methylene blue(MB)solution was treated as the response value.After the analysis of the response surface optimization,it was shown that the significance sequence of the selected 4 factors in terms of the MB degradation efficiency was arranged as follows:dopamine concentration>liquid-solid ratio>P25 titanium dioxide quality>ferric chloride quality.The optimal process parameters of fiber-carbon catalyst were affirmed as follows:the 1.7 mg/mL concentration of dopamine,the 1.2 g mass of ferric chloride,the 0.2 g mass of P25 titanium dioxide and the liquid-solid ratio of 170 mL/g.The experiment-measured average MB degra-dation efficiency performed by the optimized catalyst was 99.3%,which was nearly similar to the model-predicted value of 98.9%.It showed that the prediction model and response surface model were accurate and reliable.The results from response surface optimization could provide a good reference to design bamboo-based Fenton-like catalyst with excellent catalytic performance. 展开更多
关键词 Photo-fenton catalysis bamboo fiber carbon fiber response surface optimization methylene blue
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Wood Density Determination with the Perspective to Decarbonisation of Tropical Forest Species from the Luki Biosphere Reserve in the Democratic Republic of the Congo
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作者 Topwe Milongwe Mwene-Mbeja Luboya Muisangie Jeannette +6 位作者 Bukasa Kadima Katanku Kabongo Kanimba Junior Benjamin Kalenda Kabengela N’senda Kamulumba Kayembe Gaby Liyandja Impofi Jean-Claude Lopema Ongala Dénis Mbuyi Mpoyi Alain 《Green and Sustainable Chemistry》 CAS 2023年第2期162-169,共8页
Specimens of the forest species such as Pentaclethra macrophylla, Petersianthus macrocarpus, Pycnanthus angolensis and Terminalia superba have been sampled from LUKI Biosphere reserve in the Democratic Republic of the... Specimens of the forest species such as Pentaclethra macrophylla, Petersianthus macrocarpus, Pycnanthus angolensis and Terminalia superba have been sampled from LUKI Biosphere reserve in the Democratic Republic of the Congo in order to determine their wood density with the perspective to decarbonisation. These parameters have been found out experimentally utilizing a drying technique in an oven including techniques of immersion in an Erlenmeyer full of water. The corresponding results indicated that the four species wood density is respectively 0.85, 0.80, 0.77 and 0.51. These preliminary results will be useful in our ongoing project on carbon dioxide absorption capacity of Congo rainforest tree species. 展开更多
关键词 Carbon Dioxide Congo Rainforest Decarbonisation Wood Density
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Gapless genome assembly of azalea and multi-omics investigation into divergence between two species with distinct f lower color 被引量:3
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作者 Shuai Nie Shi-Wei Zhao +15 位作者 Tian-Le Shi Wei Zhao Ren-Gang Zhang Xue-Chan Tian Jing-Fang Guo Xue-Mei Yan Yu-Tao Bao Zhi-Chao Li Lei Kong Hai-Yao Ma Zhao-Yang Chen Hui Liu Yousry AEl-Kassaby Ilga Porth Fu-Sheng Yang Jian-Feng Mao 《Horticulture Research》 SCIE CSCD 2023年第1期193-206,共14页
The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence be... The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence between two parental species with different f lower color widely used for azalea breeding.Gapless genome assembly was generated for the yellow-f lowered azalea,Rhododendron molle.Comparative genomics found recent proliferation of long terminal repeat retrotransposons(LTR-RTs),especially Gypsy,has resulted in a 125 Mb(19%)genome size increase in species-specific regions,and a significant amount of dispersed gene duplicates(13402)and pseudogenes(17437).Metabolomic assessment revealed that yellow f lower coloration is attributed to the dynamic changes of carotenoids/f lavonols biosynthesis and chlorophyll degradation.Time-ordered gene co-expression networks(TO-GCNs)and the comparison confirmed the metabolome and uncovered the specific gene regulatory changes underpinning the distinct f lower pigmentation.B3 and ERF TFs were found dominating the gene regulation of carotenoids/f lavonols characterized pigmentation in R.molle,while WRKY,ERF,WD40,C2H2,and NAC TFs collectively regulated the anthocyanins characterized pigmentation in the red-f lowered R simsii.This study employed a multi-omics strategy in disentangling the complex divergence between two important azaleas and provided references for further functional genetics and molecular breeding. 展开更多
关键词 DIVERGENCE YELLOW COLLECTIVE
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Geology, geochronology, and exploration of the Jiama giant porphyry copper deposit (11 Mt), Tibet, China: A review
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作者 Bin Lin Ju-xing Tang +8 位作者 Pan Tang Wen-bao Zheng Yang Song Fa-qiao Li Qiu-feng Leng Zhi-chao Wang Jing Qi Miao Sun Juan David Bello Rodríguez 《China Geology》 CAS CSCD 2023年第2期338-357,I0042-I0045,共24页
Jiama,with more than 11 Mt of copper metal,is the largest porphyry-skarn copper system in the Gangdese metallogenic belt,Tibet,China,creating ideal conditions for deciphering the origin of porphyry ores in a collision... Jiama,with more than 11 Mt of copper metal,is the largest porphyry-skarn copper system in the Gangdese metallogenic belt,Tibet,China,creating ideal conditions for deciphering the origin of porphyry ores in a collision setting.Despite massive studies of the geology,chronology,petrogenesis,and ore-related fluids and their sources in Jiama,there is a lack of systematic summaries and reviews of this system.In contrast to traditional porphyry copper systems in a subduction setting,recent studies and exploration suggest that the Jiama deposit includes porphyry-type Mo-Cu,skarn-type Cu polymetallic,vein-type Au and manto orebodies.This paper reviews the latest studies on the geology,chronology,petrogenesis,fluid inclusions,and isotopic geochemistry(hydrogen,oxygen,sulfur,and lead)of the Jiama deposit.Accordingly,a multi-center complex mineralization model was constructed,indicating that multi-phase intrusions from the same magma reservoir can form multiple hydrothermal centers.These centers are mutually independent and form various orebodies or are superimposed on each other and form thick,high-grade orebodies.Finally,a new comprehensive exploration model was established for the Jiama porphyry copper system.Both models established in this study help to refine the theories on continental-collision metallogeny and porphyry copper systems. 展开更多
关键词 Copper deposit Porphyry copper system O-S-Pb isotope Multicenter complex mineralization Comprehensive exploration model Mineral exploration engineering Gangdese metallogenic belt JIAMA TIBET
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Short-Term Impact of Elemental Sulfur on Cranberry Nutrition and Crop Performance
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作者 Reza Jamaly Serge-Étienne Parent +1 位作者 Noura Ziadi Léon E. Parent 《Open Journal of Soil Science》 2023年第2期83-96,共14页
Cranberry (Vaccinium macrocarpon Ait.) is an ammophilous plant grown on acid soils (pH 4.0 - 5.5). Elemental sulfur is commonly applied at a recommended rate of 1120 kg S ha<sup>−1</sup> per pH unit to aci... Cranberry (Vaccinium macrocarpon Ait.) is an ammophilous plant grown on acid soils (pH 4.0 - 5.5). Elemental sulfur is commonly applied at a recommended rate of 1120 kg S ha<sup>−1</sup> per pH unit to acidify cranberry soils, potentially impacting the plant mineral nutrition. The general recommendation may not fit all conditions encountered in the field. Our objective was to develop an equation to predict the sulfur requirement to reach pH<sub>water</sub> of 4.2 to tackle nitrification in acidic cranberry soils varying in initial pH values, and to measure the effect of elemental sulfur on the mineral nutrition and the performance of cranberry crops. A 3-yr experiment was designed to test the effect of elemental sulfur on soil and tissue tests and on berry yield and quality. Four S treatments (0, 250, 500 and 1000 kg S ha<sup>−1</sup>) were established on three duplicated sites during two consecutive years. We ran soil, foliar tissue, berry tissue tests, and measured berry yield, size, anthocyanin content (TAcy), Brix, and firmness. Nutrients were expressed as centered log ratios to reflect nutrient interactions. Results were analyzed using a mixed model. Soil Ca decreased while soil Mn and S increased significantly (p ≤ 0.05). Sulfur showed no significant effects on nutrient balances in uprights. The S impacted negatively berry B balance, and positively berry Mn and S balances. A linear regression model relating pH change to S dosage and elapsed time (R<sup>2</sup> = 0.53) showed that to reach pH<sub>water</sub> of 4.2 two years after S application, 250 - 1000 kg S ha<sup>−1</sup> could be applied depending on initial soil pH value. The stratification of surface-applied elemental S in the soil profile should be further examined in relation to plant rooting and nutrient leaching. 展开更多
关键词 SULFUR Berry Yield and Quality Compositional Data Local Diagnosis Plant Nutrition Soil Acidification
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Effect of Organic Amendment on the Growth of Artemisia annua in the North of Côte d’Ivoire
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作者 Sarah Konaré Konan Alphonse Alui +1 位作者 Souleymane Silué André Soro 《Open Journal of Soil Science》 2023年第11期457-473,共17页
Malaria causes many deaths around the world, particularly in Africa, which ultimately affects the socio-economic development of African countries. The resistance of Plasmodium falciparum to quinine-based drugs led to ... Malaria causes many deaths around the world, particularly in Africa, which ultimately affects the socio-economic development of African countries. The resistance of Plasmodium falciparum to quinine-based drugs led to new studies showing the efficiency of new artemisin-based drugs. The molecule artemisin is extracted from Artemisia annua a plant from China that has been used for decades in traditional Chinese medicine. The purpose of this study is to improve the production of sweet wormwood (Artemisia annua) using organic fertilizers in the north of Cote d’Ivoire. To do so, a morpho-pedological characterization of the study site was firstly performed to determine the soil type and their fertility level. Then, a randomized complete block system including two factors (the quantity of compost and the plant density) was implemented to test the effect of organic amendment and plant arrangement on the growth of Artemisia annua. Six treatments were set up: a control plot (no compost) where the plants are arranged in square (T0D1) and the plants are arranged in staggered (T0D2). Then, a treatment with compost addition of 25 t/ha where the plants are arranged in square (T1D1) and in staggered (T1D2). A treatment with compost addition of 50 t/ha where plants are arranged in square (T2D1) and in staggered (T2D2). Our results showed that the soils hosting our experimentation are Arenithic Plinthic Ferrasols with a very low level of fertility, prone to leaching and erosion. T1D2 and T2D2 treatments obtained the highest yields of 2.82 t/ha and 3.91 t/ha, respectively. Our findings indicate that a high dose of organic amendment combined with a staggered plant arrangement strongly improves the biomass production of sweet wormwood. This is in agreement with previous studies showing that the addition of organic matter can restore the level of soil fertility by increasing soil porosity and the activity of micro and macroorganisms. 展开更多
关键词 Artemisia annua COMPOST Soil Fertility Korhogo Côte d’Ivoire
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Charging Mechanism of Lightning at the Molecular Level
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作者 See Leang Chin Xueliang Guo +6 位作者 Harmut Schroeder Di Song Andong Xia Fan’ao Kong Huanbin Xu Tiejun Wang Ruxin Li 《Atmospheric and Climate Sciences》 2023年第4期415-430,共16页
Cloud electrification is one of the oldest unresolved puzzles in the atmospheric sciences. Though many mechanisms for charge separation in clouds have been proposed, a quantitative understanding of their respective co... Cloud electrification is one of the oldest unresolved puzzles in the atmospheric sciences. Though many mechanisms for charge separation in clouds have been proposed, a quantitative understanding of their respective contribution in a given meteorological situation is lacking. Here we suggest and analyze a hitherto little discussed process. A qualitative picture at the molecular level of the charge separation mechanism of lightning in a thundercloud is proposed. It is based on two key physical/chemical natural phenomena, namely, internal charge separation of the atmospheric impurities/aerosols inside an atmospheric water cluster/droplet/ice particle and the existence of liquid water layers on rimers (graupels and hailstones) forming a layer of dipoles with H<sup>+</sup> pointing out from the air-water interface. Charge separation is achieved through strong collisions among ice particles and water droplets with the rimers in the turbulence of the thundercloud. This work would have significant contribution to cloud electrification and lightning formation. 展开更多
关键词 Cloud Electrification Charge Separation COLLISION Molecular Level
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寒区大坝温度场和渗流场耦合问题的非线性数值模拟 被引量:17
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作者 赖远明 刘松玉 +1 位作者 邓学钧 J.M.Konrad 《水利学报》 EI CSCD 北大核心 2001年第8期26-31,共6页
本文首先根据热传导理论和渗流理论 ,提出了带相变温度场和渗流场耦合问题的数学力学模型和控制微分方程 ,然后应用伽辽金法导出了这一问题的有限元公式 ,最后给出了一个考虑了渗流影响的寒区大坝温度场的计算实例 .该例表明渗流场对寒... 本文首先根据热传导理论和渗流理论 ,提出了带相变温度场和渗流场耦合问题的数学力学模型和控制微分方程 ,然后应用伽辽金法导出了这一问题的有限元公式 ,最后给出了一个考虑了渗流影响的寒区大坝温度场的计算实例 .该例表明渗流场对寒区大坝的温度场影响很大 ,在寒区大坝的设计时应充分考虑这一因素的影响 . 展开更多
关键词 大坝 温度场 渗流场 耦合模型 非线性 寒冷地区
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