KINETICS AND MODELING OF OIL EXTRACTION FROM VIETNAM LEMONGRASS BY STEAM DISTILLATION

Essential oils from parts of plants such as stump, flower, kernel, and seed are usually produced by extraction, distillation and mechanical press. In practice, steam distillation is commonly used for the extraction of crude essential oils since it is not only a simple process but also applicable at various scales. Furthermore, the method makes it possible for a keeping of precious components of the oils unchanged. Therefore, studies on kinetics and modeling of the essential oil steam distillation are needed for the optimization of the operating conditions, energy requirement, and the process scale-up.In this work, experiments of lemongrass (Cymbopogon Citratus) steam distillation were carried out and a kinetics model was developed for the extraction of lemongrass essential oil. Raw materials were pretreated by natural drying, primarily crushing and chopping prior to the distillation. The oil yield obtained is in the range of 2.1 – 2.9 ml/kg of raw materials. Composition of the crude oil extracted was measured by GC-MS. Measurements showing that the oil product contains 70.5 % of precious component–Citral in which Neral is 29.8 % and Geranial 40.7 %. The kinetics parameters were estimated from experimental data conducted at various operating conditions for different preparation of the raw materials. The process rate constant (extraction rate constant) describing the extraction efficiency obtained from this study is varied from 0.02 to 0.027 min-1 using first-order kinetic model

OPTIMIZATION OF GINGER OLEORESIN EXTRACTION FROM FRESH GINGER BY USING MICROWAVE - ASSISTED ENERGY

Nowadays, the active compounds from natural products are interested in not only research fields but also industrial area. Steam distillation is widely employed for the isolation of bioactive substances from natural sources. However, the process is usually long time consuming, high energy consumption and unwanted chemicals can be entrained with the main products. Microwave-assisted extraction is now recognized as an efficient extraction technique that dramatically reduces extraction time, increases yields and higher quality of the extracts can be obtained. The aim of this study is evaluation of the major factors affected by operating parameters such as concentration of solvent, radiation time, ratio of microwave power to material, volume of solvent on yield of products by microwave-assisted extraction. In addition, comparison between traditional extraction methods and microwave-assisted extraction is also carried out. The results show that application of microwave energy for the extraction of active substances from fresh ginger have faster heating, reduce thermal gradients and extraction time

Hospital waste in Hanoi

Hanoi's 36 national hospitals and specialized clinics are the largest hospitals and which have the best equipment in the country. Seriously ill patients from all provinces in the North are transferred to those hospitals for treatment. Nearly all beds are occupied. In most of those hospitals, costs are shared by the government and patients. The government supply facilities and the base salaries fore medical staff. Due to insufficient budgets, the physical infrastructure of most of hospitals is poor and backward according to international standards. Under those conditions, the waste collection and processing of clinical and non-clinical hospital also lacks of both physical infrastructure and knowledge fore management hazardous waste. This paper will review and compare the classification, processing, reuse, and recycling of waste in 24 of 36 Hanoi hospitals and specialized clinics, and also about the plan, and the role of private waste collectors and recyclers

Design and Analysis of Ternary m-sequences with Interleaved Structure by d-Transform

Multilevel sequences find more and more applications in modern modulation schemes [4QPSK, 8QPSK,16QAM..]  for the 3G ,4G system air interface [1,2].Furthermore, in modern cryptography they are also widerly used. It is also interesting to point out that the length L of these sequences are composite numbers( L=NS),that means the sequence can be easily implemented by interleaving S subsequences, each of length S.Therefore, the methods to develop multilevel sequence with interleaved structure draw a lot of attentions [3, 4]. In this contribution, a method for design and analysis of ternary m-sequences with interleaved structure is presented, based on the d-transform, Which turns out to be a very effective and versal tool for this purpose. Simulations have been made to verify the theory. We first introduce d-transform and its properties and then work out the procedure to design an interleaving sequence in d-transform. Keywords: d-transform,q-ary sequences, interleaved sequence

A Survey on Some Parameters of Beef and Buffalo Meat Quality

A survey was carried out on 13 Vietnamese Yellow cattle, 14 LaiSind cattle and 18 buffalos in Hanoi to estimate the quality of longissimus dorsi in terms of pH, color, drip loss, cooking loss and tenderness at 6 different postmortem intervals. It was found that the pH value of longissimus dorsi was not significantly different among the 3 breeds (P>0.05), being reduced rapidly during the first 36 hours postmortem, and then stayed stable. The value was in the range that was considered to be normal. Conversely, the color values L*, a* and b* tended to increase and also stable at 36 hours postmortem, except that for LaiSind cattle at 48 hours. According to L* scale, the meat of Yellow and LaiSind cattle met the normal quality but the buffalo meat was considered to be dark cutters. The tenderness of longissimus dorsi was significantly different among the breeds (P<0.05). The value was highest at 48 hours and then decreased for LaiSind and buffalo, but for Yellow cattle the value decreased continuously after slaughtering In terms of tenderness buffalo meat and Yellow cattle meat were classified as “intermediate”, while LaiSind meat was out of this interval and classified as “tough”. Drip loss ratio was increased with the time of preservation (P<0.05). The cooking loss ratio was lowest at 12 hours and higher at the next period, but there was no significant difference among the periods after 36 hours postmotem.Peer reviewe

Characterization of pig farms in Hung Yen, Hai Duong and Bac Ninh provinces

peer reviewedIn order to characterization of pig farms in the Red River Delta, a study was conducted on 90 pig farms in Hung Yen, Hai Duong and Bac Ninh provinces from June to December 2006. Results show that most of the pig farms had been built for five years with a small size (0.5 hectare per farm). The invested capital was about 300-400 millions VND per farm. Four main sow groups used in the farms included crossbred exotic sows (51.1%), crossbred sow between local and exotic breeds (14.4%), purebred Landrace and Yorkshire breeds (15.6 and 18.9%, respectively). The boars were various (Duroc 30%, Yorkshire 21%, Landrace 13%, PiÐtrain × Duroc 36% and others). The pigs farms were faced with several difficulties such as limited land, lack of invested capital, uncontrolled quality of breeding pigs, high costs of feed, poor hygiene condition and diseases

Optimization of the leaching process of the printed circuit boards production’s sludge for copper recovery via electrolysis

Copper is the main component of printed circuit boards (PCBs) which is the main part of an electronic device. The manufacture of PCBs often releases huge amount of sludge which contained copper. Derived from the demand of the industrial park about the wasted sludge treatment and the reducing of the plantation of natural mineral resources, the copper recovery process from PCBs manufacture's wasted sludge was studied. The process of copper leaching by sulfuric acid solution was studied using experimental planning methods using the simulation software Modde 5.0. The parameters were calculated and simulated to evaluate the effect of the acid concentration, leaching time, and the ratio between the solid and liquid phases on the leaching efficiency. The obtained results by simulation were compared with real experimental results. The obtained results from this study are planning in the actual deployment of the Hanoi Urban Environment One Member Limited Company in Vietnam. Keywords. Printed circuit board, copper sludge, leaching

The first successful bone marrow transplantation in Vietnam for a young Vietnamese boy with chronic granulomatous disease: a case report

BackgroundChronic granulomatous disease (CGD) is an inborn error of immunity (IEI) disorder that results from defects in the respiratory burst activity in phagocytes, leading to the inability to kill bacterial and fungal microorganisms. CGD patients usually have a high incidence of morbidity such as infections and autoinflammatory diseases and a high mortality rate. Allogeneic bone marrow transplantation (BMT) is the only definitive cure for patients who suffer from CGD.Case presentationWe report the first transplant case of chronic granulomatous disease in Vietnam. A 25-month-old boy with X-linked CGD underwent bone marrow transplantation from his 5-year-old, full-matched human leukocyte antigen (HLA)-carrier sibling after myeloablative conditioning regimen with busulfan 5.1 mg/kg/day for 4 days, fludarabine 30 mg/m2/day for 5 days, and rATG (Grafalon-Fresenius) 10 mg/kg/day for 4 days. Neutrophil was engrafted on day 13 posttransplant, donor chimerism was 100% on day 30 with the dihydrorhodamine-1,2,3 (DHR 123) flow cytometric assay test that reached 38% of the normal 45 days posttransplant. Five months after transplant, the patient was free of infection with stable DHR 123 assay at 37%, and donor chimerism remained 100%. No sign of a graft-versus-host disease had been observed posttransplant.ConclusionWe suggest that bone marrow transplantation is a safe and effectual cure for CGD patients, especially for patients with HLA-identical siblings

Village Baseline Study: Site Analysis Report for Tra Hat Village, Vinh Loi, Bac Lieu, Viet Nam (VNM 03)

This report presents data collected from the Village Baseline Study conducted on 2-4 October 2014 at the Tra Hat village, Vinh Loi district, Bac Lieu, Vietnam. Data were collected through focus group discussions and participatory resource mapping with community members in the village. The Village Baseline Study is part of the baseline activities conducted under the CGIAR Research Program on Climate Change, Agriculture, and Food Security (CCAFS) in South East Asia. The purpose is to collect data for indicators that will allow site comparability and monitoring to assess changes in terms of food security and natural resource management across time. Results show that the men and women in Tra Hat village consider farmland, rivers and canals as important natural resources. The quality, however, of land, water and wildlife habitats has declined in the last decade along with the improvement of farming techniques and intensive use of chemical fertilizers and pesticides. Infrastructures such as roads, internal canals, hospitals, schools, water supply station and electricity transformer station have improved. The future is envisioned to have improved internal canals in farmlands and a developed irrigation system, dykes and sluices to support high agriculture production. Home garden diversification was also believed to enhance food security and improve livelihood resilience. To turn the vision into reality, the community expects support from the different organizations working in the area considering current impacts of salinity intrusion and sea level rise, the need interventions of CCAFS and its partners. Strengthening the irrigation system, improving local rice variety, and introducing modern farming techniques taking into account negative impacts of climate change are major recommendation for future intervention