检索结果-南通市图书馆

3D printed millireactors for process intensification

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2020年第1期28卷 180-190页

作者： Harrson S.Santana Alan C.rodrigues Mariana G.M.Lopes Felipe N.Russo Joao L.silva Jr Osvaldir P.Taranto School of Chemical Engineering University of CampinasBrazil Federal Institute of Education Science and Technology of South of Minas GeraisBrazil

The scope of the present research aims at demonstrating the 3D printing use in the manufacturing of microchannels for chemical process applications. A comparison among digital model processing applications for 3D print(slicers) and a print layer thickness analysis were performed. The 3D print fidelity was verified in several devices, including the microchannels’ printing with and without micromixer zones. In order to highlight the 3D print potential in Chemical Engineering, the biodiesel synthesis was also carried out in a millireactor manufactured by 3D printing. The millireactor operated under laminar flow regime with a total flow rate of 75.25 ml·min^-1(increment of about 130 times over traditional microdevices used for biodiesel production).The printed millireactor provided a maximum yield of Ethyl Esters of 73.51% at 40 ℃, ethanol:oil molar ratio of7 and catalyst concentration of 1.25 wt% and residence time about 10 s. As a result of flow rate increment attained in the millireactor, the number of required units for scaling-up the chemical processes is reduced. Using the approach described in the present research, anyone could produce their own millireactor for chemical process in a simple way with the aid of a 3D printer.

关键词： Process intensification 3D printer Millireactors Micromixers Microdevices Biodiesel

Plant growth and metabolism of exotic and native Crotalaria species for mine land rehabilitation in the Amazon

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Mycelial Growth of Pleurotus Spp in Se-Enriched Culture Media

林业研究（英文版） 2024年第1期 147页

作者： Hemelyn Soares das Chagas Rafael silva Guedes Markus Gastauer Paula Godinho Ribeiro Allan Klynger da silva Lobato Cecílio Frois Caldeira Fabrício William de Ávila André rodrigues dos Reis Silvio Junio Ramos

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Advances in Microbiology 2013年第8期3卷 11-18页

作者： Marliane de Cássia Soares da silva Mateus Dias Nunes Jose Maria rodrigues da Luz Maria Catarina Megumi Kasuya Departamento de Microbiologia Federal University of VicosaCampus UFVVicosaBrazil

Selenium (Se) is an essential element to human. However, this element can be in low content in soil of some regions. Se deficiency may cause Keshan disease, thyroid dysfunction and osteoarthritis. The Se-enriched cereals are an interesting way to prevent these diseases. But, recent studies have shown that Se-enriched mushrooms are a better Se source. This occurs due to the high capacity of the fungi to absorb and transform the inorganic Se to organic forms, which are more bioavailable. Pleurotus ostreatus and Pleurotus eryngii are mushrooms species worldwide consumed and able to Se bioaccumulate. However, depending on the level of this element, it can be toxic for the fungus. Here we showed that the presence of the Se in culture medium decreases fungal growth rate, hyphae diameter and septum distance and causes alteration in color of colony. A garlic strong smell was directly proportional to Se level. P. eryngii was more tolerant to Se than P. ostreatus. So, it is important to screen this element level for Se-enriched mushroom production.

关键词： Mushrooms Colony Morphology Food Sodium Selenite Hyphae Diameter

Polymer Nanocomposites Used as Scaffolds for Bone Tissue Regeneration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2018年第8期9卷 679-697页

作者： Raquel Couto de Azevedo Goncalves Mota Emerson Oliveira da silva Lívia rodrigues de Menezes Instituto de Macromoléculas Professora Eloisa Mano Universidade Federal do Rio de JaneiroRio de JaneiroBrazil

Scaffolds are three-dimensional biocompatible structures that can mimic the properties of the extracellular matrix (ECM) of a given tissue, like mechanical support and bioactivity, which provides a platform for cellular adherence, proliferation and differentiation. Consequently, scaffolds are frequently used in tissue engineering with the intention of assisting the regeneration of a damaged tissue, and a major application in bone regeneration. An ideal scaffold needs to be biodegradable, biocompatible, and needs to match the biomechanical properties of bone. Polymers are widely used in this field because they fulfil the first two requirements. However, no polymeric material can achieve mechanical properties similar to the bone. For that reason, polymeric nanocomposites, which consist of ceramic/metallic nanoparticles dispersed in a polymer matrix, are being considered for bone scaffold fabrication in order to overcome this problem, since nanoparticles are known to improve composite mechanical strength, and enhance other properties.

关键词： Scaffolds Polymer Nanocomposites Nanoparticles Bone Tissue Engineering

Symbolic Control of Hybrid Systems from Signal Temporal Logic Specifications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Guidance, Navigation and Control 2021年第2期1卷 60-84页

作者： Rafael rodrigues da silva Vince Kurtz Hai Lin Department of Electrical Engineering University of Notre DameNotre DameIN 46556USA

In safety-critical systems,it is desirable to automatically synthesize controllers for complex tasks with guaranteed safety and *** much progress has been made through controller synthesis from temporal logic speci-cations,existing approaches generally require conservative assumptions and do not scale well with system *** propose a scalable,provably complete algorithm that synthesizes continuous trajectories for hybrid systems to satisfy temporal logic ***-cally,we harness highly e±cient Boolean satis-ability(SAT)and Linear Programming(LP)solvers to-nd trajectories that satisfy nonconvex Signal Temporal Logic(STL)speci-cations for a class of high dimensional hybrid *** proposed design algorithms are proven sound and complete,and are validated in simulation experiments.

关键词： Signal temporal logic motion planning hybrid systems trajectory synthesis symbolic control

Prognostic Factors, Incidence and Management for Acute Variceal Bleeding in the Liver Transplantation Era

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Surgical Science 2011年第4期2卷 198-203页

作者： élio rodrigues da silva Ilka de Fátima Santana Ferreira Boin Eurípedes Soares Filho Patrícia Alexsandra Nunes Barros Rodrgiues Benedito Borges da silva 不详

Background: Gastroesophageal varices are the most common and clinically important part of the portosys-temic collaterals due to their tendency to rupture and cause massive gastrointestinal bleeding. Objective The aim of this work was to evaluate retrospectively the incidence and the factors of prediction for the treatment of bleeding by gastroesophageal varices in the patients attended in the Emergency Room of the Hospital State University of Campinas (Brazil) from the last ten years. Methods: The method used here consisted of a descriptive and retrospective study carried out from the analyses of the medical records of 769 patients with upper gastrointestinal bleeding of which 220 were admitted because of upper gastrointestinal bleeding caused by gastroesophageal varices during this same period. Results: The results showed that the gastroe-sophageal varices appeared in 28.6% of the patients and they were the second most common cause of upper gastrointestinal bleeding. While evaluating factors such as age, sex and the common individual records, it was proved that this disease occurs mainly among people between the third and the fifth decade of life, with the great majority of cases occurring in the fourth decade (29.2%), of which 76.8% were male. There was an association of hematemesis and melena in the admission of 57.7% of the patients and even ascites was a common diagnosis in 48.2% of them. Most of these patients (40%) were classified as Child class B at admis-sion. The early endoscopic exam was used for 96.8% of them and showed the presence of F3 varices in 38.5%, CB varices in 25.1% and RCS varices in 12.6%. Most of these varices (41.5%) were situated in the distal third of the esophagus. The most used pharmacological treatment was based on octreotide in 45.9% of the patients. They received 0.05 mg of intravenous octreotide and a maintenance dose of 1 mg per day in 98.6% of the cases, with efficacy in 74.2% of the patients. The tamponade with Sengstaken-Blakemo

关键词： Liver Transplantation Portal Vein Thrombosis Surgical Technique

The Difference of the Impact of Elective Cholecystectomy Surgery in the Immune Response

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Surgical Science 2018年第8期9卷 243-247页

作者： Rosamaria rodrigues Gomes Manoel Messias Lima Neto Ayrton silva Alves Cristiane Monteiro da Cruz Medical School Centro Universitário Cesmac Maceió Brazil

Introduction: The inflammatory response is essential to initiate the healing process, and in this response there is an increase in white blood cells and pro-inflammatory compounds. Creactive proteins (CRP), together with the blood leukocyte count, have been used to study the immune response. Due to the risk of infection and exacerbated inflammatory response of the patients undergoing surgical procedure, it is relevant to investigate the pre and postoperative inflammatory response of those individuals. Objective: To determine the difference in the impact of elective cholecystectomy surgery on the patient’s immune response. Methods: The present study was cross-sectional, where a group included patients who underwent elective cholecystectomy procedure. Patients who were pregnant, under 18 years, of indigenous communities or with other conditions that depress the immune system, as well as those on immunosuppressive medications, were excluded. Results: CRP and leukocyte counts indicated a mean increase of 5.97-fold (95% CI 3.76 to 8.34, SD 6.98) and 1.97-fold (95% CI 1.71 to 2.24, SD 1.97) respectively, both being evaluated before and after surgery. Discussion: In the present study, to avoid a possible methodological bias, it was chosen to evaluate the patients submitted to videolaparoscopic cholecystectomy only and the hypothesis was confirmed that there is an increase in CRP and leukocyte count as a response to surgical trauma. Conclusion: There was an elevation of the inflammatory markers in patients submitted to surgical trauma when comparing the exams collected in the preoperative period and after the surgical aggression.

关键词： Cholecystectomy Inflammation Leukocytes C-Reactive Protein

Effect of the Addiction of Metal Oxide Nanoparticles on the Physical, Chemical and Thermal Properties of PVA Based Nanocomposites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2018年第5期9卷 473-488页

作者： Raquel Couto de Azevedo Gonç alves Mota Emerson Oliveira da silva Lí via rodrigues de Menezes Instituto de Macromolé culas Professora Eloisa Mano Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil

In this study, poly(vinyl alcohol) (PVA)-based nanocomposites consisting of metallic oxide nanoparticles (TiO2, ZnO, ZrO2) were obtained from an aqueous solution of 7% PVA, in order to compare the microstructural, and physical properties of bionanocomposite films reinforced with various loading contents (0.1%, 0.2% and 0.3% w/w). They were evaluated regarding their molecular toughness through Nuclear Magnetic Resonance (NMR), regarding their chemical structural through Fourier Transform Infrared Spectroscopy (FTIR), regarding their crystallinity throught X-ray Diffraction (XRD), and regarding termal properties through Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The NMR results showed that the smallest concentrations of these oxides have a tendency to disperse better in the polymeric matrix, improving the structural toughness. Besides, changes in the termal resistance of the material were found with the use of TGA and DSC.

关键词： Poly(vinyl alcohol) Nanocomposites Metallic Oxides Titanium Oxide Zirconium Oxide Zinc Oxide

Yield, Water Use Efficiency and Physiological Characteristic of “Tommy Atkins” Mango under Partial Rootzone Drying Irrigation System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2015年第13期7卷 1029-1037页

作者： Marcelo Rocha dos Santos Breno Rosa Neves Bismarc Lopes da silva Sérgio Luiz rodrigues Donato Instituto Federal de Educa ç o Ciência e Tecnologia Baiano Campus Guanambi Bahia Brazil

This study was conducted to evaluate the yield, water use efficiency and physiologic characteristics of “Tommy Atkins” mango under partial rootzone drying. The experiment was carried out in an orchard of mango in the irrigated perimeter of Ceraíma, BA. Five treatments and six repetitions were used with one tree per experimental plot: 01—Full Irrigation, 100% of ETc, 02—100% of ETc with frequency of alternance (FA) of 15 days, 03—80% ETc with FA of 15 days, 04—60% of ETc with FA of 15 days, 05—40% ETc with FA of 15 days. The treatments were conductedfrom the beginning of flowering to the harvest of mango in an orchard irrigated by drip. There was no significant reduction in productivity of “Tommy Atkins” mango under PRD up to 40% of ETc and PRD with 40% ETc resulted in greater water use efficiency. There was no significant difference among the averages of photosynthetically active radiation, Qleaf;leaf temperature, Tl;internal CO2 concentration, Ci;transpiration, E;stomatal conductance, gs;photosynthesis, A;carboxylation efficiency, A/Ci;quantum efficiency of photosynthesis, A/Qleaf and instantaneous water use efficiency, A/E between full irrigation and PRD with different water depth. The increase in leaf temperature causes reduction in A/Qleaf and A/E, however, it increases the transpiration. Increased gs results in higher rates of E, A and A/Ci. The use of the PRD with 40% of ETc causes no interference in gas exchange, maintains the yield and increases water use efficiency in “Tommy Atkins” mango tree.

关键词： Irrigation Strategy Mangifera Regulated Deficit Irrigation