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A new green process for biodiesel production from waste oils via catalytic distillation using a solid acid catalyst-Modeling, economic and environmental analysis

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Green Energy & Environment 2016年第1期1卷 62-74页

作者： Aashish Gaurav Flora t.t.Ng Garry l.Rempel Department of Chemical Engineering University of Waterloo

the challenges in the chemical processing industry today are environmental concerns, energy and capital costs. Catalytic distillation(CD) is a green reactor technology which combines a catalytic reaction and separation via distillation in the same distillation column. Utilization of CD in chemical process development could result in capital and energy savings, and the reduction of greenhouse gases. the efficacy of CD and the economic merits, in terms of energy and equipment savings, brought by CD for the production of biodiesel from waste oil such as yellow grease is quantified. Process flow sheets for industrial routes for an annual production of 10 million gallon AStM purity biodiesel in a conventional process(reactor followed by distillation) and CD configurations are modeled in Aspen Plus. Material and energy flows, as well as sized unit operation blocks, are used to conduct an economic assessment of each process. total capital investment, total operating and utility costs are calculated for each process. the waste oil feedstock is yellow grease containing both triglyceride and free fatty acid. Both transesterification and esterification reactions are considered in the process simulations. Results show a significant advantage of CD compared to a conventional biodiesel processes due to the reduction of distillation columns, waste streams and greenhouse gas emissions. the significant savings in capital and energy costs together with the reduction of greenhouse gases demonstrate that process intensification via CD is a feasible and new green process for the biodiesel production from waste oils.

关键词： Yellow grease Catalytic distillation Aspen plus economic analyzer Process intensification

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High-magnetic-field induced charge order in high-t_c cuprate superconductors

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Chinese Physics B 2019年第11期28卷 25-42页

作者： l X Zheng J li t WU Hefei National laboratory for Physical Science at Microscale University of Science and Technology of ChinaHefei 230026China Key laboratory of Strongly-coupled Quantum Matter Physics University of Science and Technology of ChinaChinese Academy of SciencesHefei 230026China CAS Center for Excellence in Superconducting Electronics(CENSE) Shanghai 200050China CAS Center for Excellence in Quantum Information and Quantum Physics Hefei 230026China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

In the last few years, charge order and its entanglement with superconductivity are under hot debate in high-tc community due to the new progress on charge order in high-tc cuprate superconductors YBa2Cu3O6+x. Here, we will briefly introduce the experimental status of this field and mainly focus on the experimental progress of high-field nuclear magnetic resonance(NMR) study on charge order in YBa2Cu3O6+x. the pioneering high-field NMR work in YBa2Cu3O6+x sets a new stage for studying charge order which has become a ubiquitous phenomenon in high-tc cuprate superconductors.

关键词： charge order cuprates nuclear magnetic resonance YBa2Cu3O6+x superconductors competing order

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Emergent phenomena in manganites under spatial confinement

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Chinese Physics B 2013年第1期22卷 1-11页

作者：沈健 t.Z.Ward l.F.Yin State Key laboratory of Surface Physics and Department of Physics Fudan University Department of Physics and Astronomy The University of Tennessee Materials Science and technology Division Oak Ridge National Laboratory

It is becoming increasingly clear that the exotic properties displayed by correlated electronic materials such as high- tc superconductivity in cuprates, colossal magnetoresistance （CMR） in manganites, and heavy-fermion compounds are intimately related to the coexistence of competing nearly degenerate states which couple simultaneously active degrees of freedom---charge, lattice, orbital, and spin states. the striking phenomena associated with these materials are due in a large part to spatial electronic inhomogeneities, or electronic phase separation （EPS）. In many of these hard materials, the functionality is a result of the soft electronic component that leads to self-organization. In this paper, we review our recent work on a novel spatial confinement technique that has led to some fascinating new discoveries about the role of EPS in manganites. Using lithographic techniques to confine manganite thin films to length scales of the EPS domains that reside within them, it is possible to simultaneously probe EPS domains with different electronic states. this method allows for a much more complete view of the phases residing in a material and gives vital information on phase formation, movement, and fluctuation. Pushing this trend to its limit, we propose to control the formation process of the EPS using external local fields, which include magnetic exchange field, strain field, and electric field. We term the ability to pattern EPS ＂electronic nanofabrication.＂ this method allows us to control the global physical properties of the system at a very fundamental level, and greatly enhances the potential for realizing true oxide electronics.

关键词： manganites metal-insulator transition electrical transport electronic phase separation

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Water solubility enhancements of pyrene by single and mixed surfactant solutions

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Journal of Environmental Sciences 2001年第4期13卷 491-496页

作者： Zhu, l.-z. Chiou, C.t. Department of Environmental Science Zhejiang University Hangzhou 310028 China

Water solubility enhancements of pyrene by both single-surfactant and mixed-surfactant solutions were compared and evaluated. the solubility of pyrene in water was greatly enhanced by each of triton X-100 (tX100), triton X-405 (tX405), Brij 35 and SDS, in which the water solubility enhancements increased with increasing surfactant concentrations. the extent of solubility enhancements at surfactant concentrations below. the CMC is the order of tX100 > Brij 35 > tX405 > SDS; the sequence at surfactant concentrations above the CMC is tX100 > Brij 35 > SDS > tX405. Pyrene was solubilized synergistically by anionic-nonionic mixed surfactant solutions, especially at low surfactant concentrations. the synergistic power of the mixed surfactants is SDS-tX405 > SDS-Brij 35 > SDS-tX100. the synergism as noted is attributed to increasing Kmc and/or decreasing the CMC of the mixed surfactant solution. For SDS-tX405 and SDS-Brij 35 mixed surfactant solutions, an increase in Kmc is coupled with a decrease in the CMC; for SDS-tX100, only a decreased in the CMC value is noted. Mixed-surfactant solutions may improve the performance of the surfactant-enhanced remediation (SER) of soils by increasing the bioavailability and biodegradation of non-aqueous-phase organic pollutants and reducing the level of surfactant pollution and remediation expenses.

关键词： Biodegradation Concentration (process) Solubility Water

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Operation Strategies for Coordinating Battery Energy Storage with Wind Power Generation and their Effects on System Reliability

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 190-198页

作者： thais P.teixeira Carmen l.t.Borges the Federal University of Rio de Janeiro Rio de JaneiroBrazil

the variability of wind power generation requires the allocation of a flexible energy reserve which is capable of compensating for possible imbalances between the load and generation. to reduce the variability of wind power generation and loss of load in generation deficit, we propose operation strategies for coordinating battery energy storage with wind power generation. the effects of the operation strategies on system reliability are evaluated by the developed computation model that represents the main aspects and operation limitations of the batteries. the performance evaluation of the power system is based on the composite reliability indices of loss of load probability(lOlP) and expected energy not supplied(EENS), which is calculated through sequential Monte Carlo simulation. tests are performed by the developed model with a tutorial system consisting of five busbars and the IEEE RtS system. the results show that the use of large-scale batteries is an alternative to physically guarantee the wind power plants and to act as an operation reserve to reduce the risk of loss of load.

关键词： Energy storage wind power generation power system reliability Monte Carlo simulation

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Mast cell activation syndrome:An up-to-date review of literature

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World Journal of Clinical Pediatrics 2024年第2期13卷 104-113页

作者： ÖnerÖzdemir Gökçe Kasımoğlu Ayşegül Bak Hüseyin Sütlüoğlu Süreyya Savaşan Department of Pediatric Allergy and Immunology Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Kocaeli City HospitalKocaeli 50123Türkiye Department of Pediatrics Children’s Hospital of MichiganHematology/OncologyCentral Michigan University College of MedicineMount PleasantMI 48859United States Barbara Ann Karmanos Cancer Institute Wayne State UniversityDetroitMI 12345United States

Mast cells are a subtype of white blood cells and are involved in the immune *** cells contain many chemical substances called mediators,which are involved in the allergic *** fact that mast cells play a role in many events that require urgent intervention,especially anaphylaxis,has led to a more detailed study of these *** diseases also caused by dysfunctions of mast cells have been examined in many *** instance,mast cell activation syndrome is known as an augmented number of cells due to decreased cell death,resulting in clinical symptoms affecting many *** main common symptoms include flushing,hypotension,urticaria,angioedema,headache,vomiting and *** the underlying mechanism is not yet clearly known,we aim to review the literature in a broad perspective and bring together the existing knowledge in the light of the literature due to the diversity of its involvement in the body and the fact that it is a little known syndrome.

关键词： Mast cell Mast cell activation syndrome tryptase Histamine

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therapeutic effects of tender coconut water on oxidative stress in fructose fed insulin resistant hypertensive rats

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Asian Pacific Journal of tropical Medicine 2012年第4期5卷 270-276页

作者： D Bhagya l Prema t Rajamohan Department of Biochemistry University of Kerala.Kariavattom CampusKeralaTrivandrum695581India Department of Food Science and Nutrition Agricultural CollegeVellayaniTrivandrumKeralaIndia Department of Biochemistry University of Kerala Kariavattom CampusKeralaTrivandrum695581India

Objective:to investigate whether tender coconut water(tCW) mitigates oxidative stress in fructose fed hypertensive ***:Male Sprague Dawley rats were fed with fructose rich diet and treated with tCW(4 ml/100 g of body weight) for 3 subsequent *** blootl pressure was measured every three days using the indirect tail cuff *** the end of the experimental period,plasma glucose and insulin,serum triglycerides and free fatly acids, lipid peroxidation markers(MDA,hydroperoxides and conjugated dienes) and the activities of antioxidant enzymes were analyzed in all the ***:treatment with tCW significandy lowered the systolic blood pressure and reduced serum triglycerides and free fatty *** glucose and insulin levels and lipid peroxidation markers such as MDA,hydroperoxides and conjugated dienes were significantly reduced in fructose fed rats treated with *** of antioxidant enzymes are up regulated significantly in tCW treated *** analysis of liver showed that tCW treatment reduced the lipid accumulation and inflammatory infiltration without any significant hepatocellular ***:the overall results suggest that, tCW treatment could prevent and reverse high blood pressure induced by high fructose diet probably by inhibition of lipid peroxidation,upregulation of antioxidant status and improved insulin sensitivity.

关键词： tender coconut water Hypertension Oxidative stress Hyperinsulinemia lipid peroxidation Histopathology

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Association between Placental Malaria and Severe Pre-Eclampsia in two University Hospitals of Yaounde City

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Open Journal of Obstetrics and Gynecology 2024年第9期14卷 1488-1511页

作者： Ayissi Gregory Astrid Ruth Ndolo Kondo Ndoumba Afouba Alice Noa Ndoua Claude Cyrille Essiben Félix Meka Esther Belinga Etienne Metogo Junie Engo Engo Samuel Désiré Bodo Edmond lemaire tchente Nguefack Charlotte Foumane Pascal Mboudou Emile télésphore Department of Obstetrics and Gynecology Faculty of Medicine and Biomedicals Sciences University of Yaound I Yaounde Cameroon Department of Obstetrics and Gynecology Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon Department of Morphological and Anatomo-Pathological Sciences Faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon. Department of Morphological and Anatomo-Pathological Sciences Faculty of Medicine and Biomedicals Sciences University of Yaound I Yaounde Cameroon

Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: the objective of our study was to investigate the association between placental malaria lesions and severe pre-eclampsia. Methodology: We conducted a prospective analytical cross-sectional study in two University Hospitals in the city of Yaounde (Yaounde Central Hospital and the Gynaecological Obstetrics and Paediatrics Hospital), and in the laboratory of the Centre Pasteur in Yaounde over an eight-month period (1st January 2021 – 1st September 2021). All patients with pre-eclampsia diagnosed according to the criteria of the International Society for the Study of Hypertension (ISSHP) and free of chronic metabolic or infectious pathology were included in this study. the patients were divided into two groups: group 1 (mild pre-eclampsia) and group 2: severe pre-eclampsia. Socio-demographic, clinical and histopathological characteristics specific to pre-eclampsia and placental malaria were investigated. Statistical analysis was performed with SPSS 23.0 software, Chi 2 was used to compare categorical variables, Student t-test was used to compare means, and logistic regression was used to assess the association between placental malaria lesions and PES. Results: the mean age of our study population was 29.93 ± 7.36 years versus 28.28 ± 7.18 years in patients with mild and severe pre-eclampsia respectively. Pre-eclampsia placental lesions (accelerated villous maturation, infarction) were significantly greater in patients with severe pre-eclampsia (p Conclusion: Placental malaria lesions were significantly associated with severe pre-eclampsia and increased the risk of developing severe pre-eclampsia placental lesions by a factor of 10.

关键词： Mild Pre-Eclampsia Severe Pre-Eclampsia Malaria Placental lesions Association

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A StAtIStICAl INVEStIGAtION OF FAtIGUE CRACK INItIAtION AND GROWtH PROCESS BASED UPON A lARGE SAMPlE SIZE EXPERIMENt

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Acta Mechanica Solida Sinica 1996年第1期9卷 1-12页

作者： Min, l Ning, t Yang, QX NORtHWEStERN POlYtECH UNIV DEPT AIRCRAFT ENGNXIAN 710072PEOPLES R CHINA

After finishing 102 replicate constant amplitude crack initiation and growth tests on ly12-CZ aluminum alloy plate, a statistical investigation of the fatigue crack initiation and growth process is conducted in this paper. According to the post-mortem fractographic examination by scanning electron microscopy (SEM), some qualitative observations of the spacial correlation among fatigue striations are developed to reveal the statistical nature of material intrinsic inhomogeneity during the crack growth process. From the test data, an engineering division between crack initiation and growth is defined as the upper limit of small crack. the distributions of crack initiation life N-i, growth life N, and the statistical characteristics of crack growth rate da/dN are also investigated. It is hoped that the work will provide a solid test basis for the study of probabilistic fatigue, probabilistic fracture mechanics, fatigue reliability and its engineering applications.

关键词： crack initiation crack growth statistical nature large sample size

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兼顾通信效率与效用的自适应高斯差分隐私个性化联邦学习

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计算机学报 2024年第4期47卷 924-946页

作者：李敏肖迪陈律君重庆大学计算机学院重庆400044

近年来,由于联邦学习中的通信参数(或梯度)会给参与方本地敏感数据带来重大的隐私泄露风险,联邦学习隐私保护引起了广泛的关注.然而,梯度交换频繁、数据分布异构、参与方本地硬件资源受限等一系列不可避免的因素给联邦学习隐私保护增加... 详细信息

近年来,由于联邦学习中的通信参数(或梯度)会给参与方本地敏感数据带来重大的隐私泄露风险,联邦学习隐私保护引起了广泛的关注.然而,梯度交换频繁、数据分布异构、参与方本地硬件资源受限等一系列不可避免的因素给联邦学习隐私保护增加了挑战难度.为了以一种统一的方式同时有效地解决数据隐私、模型效用、通信效率以及参与方数据非独立同分布等四个方面的问题,本文提出了一种新的兼顾通信效率与效用的自适应高斯差分隐私个性化联邦学习(Communication-efficient and Utility-aware Adaptive Gaussian Differential Privacy for Personalized Federated learning,CUAG-PFl)方法.具体而言,本文提出一种动态层级压缩模型梯度的方案先为通信模型梯度每一层动态生成特定的压缩率,再根据压缩率构造对应的确定性二进制测量矩阵去除梯度冗余信息.随后,通过同时优化裁剪阈值、敏感度和噪声尺度等隐私相关参数来对压缩的模型梯度执行自适应高斯差分隐私操作.此外,本文对CUAG-PFl进行了严格的隐私分析.为了验证CUAG-PFl在隐私、效用、通信效率以及个性化四个方面的优势,本文在CIFAR-10和CIFAR-100两个真实联邦数据集上进行了大量实验模拟、对比和分析,结果表明CUAG-PFl能够提高参与方本地数据隐私性、通信效率和模型效用,同时解决了数据非独立同分布的问题.特别地,即使在隐私预算仅为0.92且上行通信量减少68.6%时,CUAG-PFl因隐私保护和梯度压缩所引起的模型效用损失仅为1.66%.

关键词：自适应高斯差分隐私隐私-效用权衡动态层级压缩通信高效个性化联邦学习隐私计算

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