scholarly journals Towards combinatorial mixing devices without any pumps by open-capillary channels: fundamentals and applications

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Marie Tani ◽  
Ryuji Kawano ◽  
Koki Kamiya ◽  
Ko Okumura
Keyword(s):  
Scaling Laws ◽  
Low Cost ◽  
Field Studies ◽  
Bromothymol Blue ◽  
Precursor Film ◽  
Micro Channels ◽  
Green Florescent Protein ◽  
Statics And Dynamics ◽  
Simple Scaling ◽  
Pharmaceutical Industries

Abstract In chemistry, biology, medical sciences and pharmaceutical industries, many reactions have to be checked by transporting and mixing expensive liquids. For such purposes, microfluidics systems consisting of closed channels with external pumps have been useful. However, the usage has been limited because of high fabrication cost and need for a fixed setup. Here, we show that open-capillary channels, which can be fabricated outside a clean room on durable substrates and are washable and reusable, are considerably promising for micro-devices that function without pumps, as a result of detailed studies on the imbibition of open micro-channels. We find that the statics and dynamics of the imbibition follow simple scaling laws in a wide and practical range; although a precursor film obeying a universal dynamics appears in the vertical imbibition, it disappears in the horizontal mode to make the design of complex micro-channel geometry feasible. We fabricate micro open-channel devices without any pumps to express the green florescent protein (GFP) by transporting highly viscous solutions and to accomplish simultaneous chemical reactions for the Bromothymol blue (BTB) solution. We envision that open-capillary devices will become a simple and low-cost option to achieve microfluidic devices that are usable in small clinics and field studies.

HOUSEHOLD WATER BALANCE AND ASSESSMENT OF WATER VOLUME FOR IRRIGATION IN AGRO LANDSCAPES OF THE KYZYLSU-YUZHNAYA BASIN

2020 ◽  
pp. 102-109
Author(s):  
D.KH. DOMULLODZHANOV ◽  
◽  
R. RAHMATILLOEV
Keyword(s):  
Water Balance ◽  
River Basin ◽  
Water Use ◽  
Storage Systems ◽  
Low Cost ◽  
Field Studies ◽  
Water Volume ◽  
Land Productivity ◽  
Household Water ◽  
And Storage

The article presents the results of the field studies and observations that carried out on the territory of the hilly, low-mountain and foothill agro landscapes of the Kyzylsu-yuzhnaya (Kyzylsu-Southern) River Basin of Tajikistan. Taking into account the high-altitude location of households and the amount of precipitation in the river basin, the annual volumes of water accumulated with the use of low-cost systems of collection and storage of precipitation have been clarified. The amount of water accumulated in the precipitation collection and storage systems has been established, the volume of water used for communal and domestic needs,the watering of livestock and the amount of water that can be used to irrigate crops in the have been determined. Possible areas of irrigation of household plots depending on the different availability of precipitation have been determined. It has been established that in wet years (with precipitation of about 10%) the amount of water collected using drip irrigation will be sufficient for irrigation of 0.13 hectares, and in dry years (with 90% of precipitation) it will be possible to irrigate only 0.03 ha of the household plot. On the basis of the basin, the total area of irrigation in wet years can be 4497 ha, and in dry years only 1087 ha. Taking into account the forecasts of population growth by 2030 and an increase in the number of households, the total area of irrigation of farmlands in wet years may reach 5703 hectares,and in dry years – 1379 hectares. Growing crops on household plots under irrigation contributes to a significant increase in land productivity and increases the efficiency of water use of the Kyzylsu-yuzhnaya basin.

scholarly journals Design of Mechanism and Preliminary Field Validation of Low-Cost Transfemoral Rotator for Use in the Developing World

2016 ◽  
Author(s):  
Matthew L. Cavuto ◽  
Matthew Chun ◽  
Nora Kelsall ◽  
Karl Baranov ◽  
Keriann Durgin ◽  
...  
Keyword(s):  
Developing World ◽  
Low Cost ◽  
Field Studies ◽  
Field Validation ◽  
User Testing ◽  
Common Solution ◽  
Locking Mechanism ◽  
Medial Rotation ◽  
Transfemoral Amputees ◽  
And Function

Transfemoral (above-knee) amputees face a unique and challenging set of restrictions to movement and function. Most notably, they are unable to medially rotate their lower-leg and subsequently cross their legs. The best and most common solution to this issue today is a transfemoral rotator, which allows medial rotation of the leg distal to the knee through a lockable turntable mechanism. However, currently available transfemoral rotators can cost thousands of dollars, and few equivalent technologies exist in the developing world. This paper, supported by the results of field studies and user testing, establishes a framework for the design of a low-cost and easily manufacturable transfemoral rotator for use in the developing world. Two prototypes are presented, each with a unique internal locking mechanism and form. A preliminary field study was conducted on six transfemoral amputees in India and qualitative user and prosthetist feedback was collected. Both prototypes successfully allowed all subjects to complete tasks such as crossing legs, putting on pants, and tying shoes while maintaining functionality of walking and standing. Future iterations of the mechanism will be guided by a combination of the most positively received features of the prototypes and general feedback suggestions from the users.

scholarly journals A Comparative Study of COD Removal Efficacy from Pharmaceutical Wastewater by Areca Nut Husk Produced and Commercially Available Activated Carbons

2021 ◽  
pp. 47-56
Author(s):  
Sharmin Akter ◽  
Ferdousi Sultana ◽  
Md. Rakibul Kabir ◽  
Partha Pratim Brahma ◽  
Atkeeya Tasneem ◽  
...  
Keyword(s):  
Experimental Data ◽  
Activated Carbon ◽  
Organic Contaminants ◽  
Activated Carbons ◽  
Low Cost ◽  
Oxygen Demand ◽  
Areca Nut ◽  
Pharmaceutical Wastewater ◽  
Adsorption Processes ◽  
Pharmaceutical Industries

Pharmaceutical industries in Bangladesh are considered as one major industrial as well as environmental pollution problems which discharge a significant amount of organic contaminants in the environment hence require advanced treatment technologies to decontaminate pharmaceutical wastewater. In the present investigation, areca nut husk treated activated carbon (ANHC) was used as an adsorbent to remove chemical oxygen demand (COD) from pharmaceutical effluent as well as a comparative adsorption efficiency with commercial activated carbon (CAC) was performed.  The batch experiments were carried out in a laboratory scale. The materials also evaluated for different adsorbent dosages and contact times. The experiment revealed a removal percentage up to 70% for ANHC and 90% for CAC for 3g of adsorbents in 180 min. The adsorption processes were satisfactorily described by pseudo-second-order (PSO) kinetic model which shows a better fitting with the maximum regression coefficient for both adsorbents. The results show that Langmuir model best described the experimental data with a highest correlation coefficient (R2=0.9856 for ANHC and 0.9993 for CAC) compared to Freundlich model and the experimental data showed asorption capacity of 36.549 and 64.935 mg/g for ANHC and CAC, correspondingly. According to the adsorption studies, the results revealed that COD adsorption process followed by the monolayer chemisorption mechanisms. The results revealed that ANHC adsorbent is potentially low cost and environmental friendly adsorbent for the removal of organic matter from pharmaceutical effluent.

Micro Thermal Engines: Is There Any Room at the Bottom?

1999 ◽  
Author(s):  
Richard B. Peterson
Keyword(s):  
Heat Transfer ◽  
Scaling Laws ◽  
Critical Role ◽  
Heat Engine ◽  
Engine Performance ◽  
Characteristic Size ◽  
Operating Efficiency ◽  
Simple Scaling ◽  
Small Structure ◽  
Micro Heat Engine

Abstract Richard P. Feynman introduced the field of microscale and nanoscale engineering in 1959 by giving a talk on how to make things very small. Feynman’s premise was that no fundamental physical laws limit the size of a machine down to the microscopic level. Is this true for all types of machines? Are micro thermal devices fundamentally different than mechanically-based machines with respect to their scaling laws? This paper demonstrates that micro thermal engines do indeed suffer serious performance degradation as their characteristic size is reduced. A micro thermal engine, and more generally, any thermally-based micro device, depends on establishing a temperature difference between two regions within a small structure. In this paper, the performance of a micro thermal engine is explored as a function of the characteristic length parameter, L. In the development, the important features of thermal engines are discussed in the context of developing simple scaling laws predicting the dependency of the operating efficiency on L. After this is accomplished, a general model is derived for a heat engine operating between two temperature reservoirs and having both intrinsic and extrinsic sources of irreversibility, i.e. thermal conductances and heat leakage paths for the heat flow. With this model and typical numerical values for the conductances, micro heat engine performance is predicted as the characteristic size is reduced. This paper demonstrates that under at least one particular formulation of the problem, there may indeed be some room at the bottom. However, heat transfer does play a critical role in determining micro engine performance and depending on how the heat transfer through the engine is modeled, vanishingly small efficiencies can result as the characteristic engine size goes to zero.

scholarly journals Feasibility Study for a Chemical Process Particle Size Characterization System for Explosive Environments Using Low Laser Power

Micromachines ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 911
Author(s):  
Jesse Ross-Jones ◽  
Tobias Teumer ◽  
Susann Wunsch ◽  
Lukas Petri ◽  
Hermann Nirschl ◽  
...  
Keyword(s):  
Light Scattering ◽  
Low Cost ◽  
Particle Diameter ◽  
Feasibility Studies ◽  
Fast Response ◽  
The Novel ◽  
Micro Channels ◽  
Size Characterization ◽  
Novel Method ◽  
Particle Size Characterization

The industrial particle sensor market lacks simple, easy to use, low cost yet robust, safe and fast response solutions. Towards development of such a sensor, for in-line use in micro channels under continuous flow conditions, this work introduces static light scattering (SLS) determination of particle diameter using a laser with an emission power of less than 5 µW together with sensitive detectors with detection times of 1 ms. The measurements for the feasibility studies are made in an angular range between 20° and 160° in 2° increments. We focus on the range between 300 and 1000 nm, for applications in the production of paints, colors, pigments and crystallites. Due to the fast response time, reaction characteristics in microchannel designs for precipitation and crystallization processes can be studied. A novel method for particle diameter characterization is developed using the positions of maxima and minima and slope distribution. The novel algorithm to classify particle diameter is especially developed to be independent of dispersed phase concentration or concentration fluctuations like product flares or signal instability. Measurement signals are post processed and particle diameters are validated against Mie light scattering simulations. The design of a low cost instrument for industrial use is proposed.

Weed-Control Systems for Peanut Grown as a Biofuel Feedstock

2008 ◽  
Vol 22 (4) ◽  
pp. 584-590 ◽  
Author(s):  
Wilson H. Faircloth ◽  
Jason A. Ferrell ◽  
Christopher L. Main
Keyword(s):  
Control Systems ◽  
Weed Control ◽  
Low Cost ◽  
Field Studies ◽  
Peanut Oil ◽  
Oil Yield ◽  
Oilseed Crop ◽  
Application Timing ◽  
The Cost ◽  
On Farm

Peanuts are not often used as a true oilseed crop, especially for the production of fuel. However, peanut could be a feedstock for biodiesel, especially in on-farm or small cooperative businesses, where producers can dictate the cost of making their own fuel. Field studies were conducted in 2005 and 2006 to assess low-cost weed-control systems for peanuts that would facilitate the economic viability of peanut biodiesel. Four preselected herbicide costs ranging from $25 to $62/ha and two application timings were compared with nontreated ($0/ha) and typical ($115/ha) herbicide programs for weed control and peanut oil yield. A peanut oil yield goal of 930 L/ha was exceeded with multiple low-cost herbicide systems in 3 of 4 site–yr. The main effect of application timing was only significant for a single site–year in which oil yield increased linearly with cost of the PRE and POST weed-control system. An herbicide cost of $50/ha, using PRE and POST applications, was consistently among the highest in oil yield, regardless of site–year, exceeding the typical (high value) programs in 3 of 4 site–yr. Use of reduced rates of imazapic (0.5× or 0.035 kg ai/ha) was detrimental in 2 of 4 site–yr. Weed control, and thus oil yields, were most dependent on species present at each location and not on input price. Data from this series of studies will allow researchers and entrepreneurs to more accurately assess the viability and sustainability of peanut biodiesel.

scholarly journals Removal of Levafix Red from Aqueous Solution with Treated Jute Stick and its Relevance to Pharmaceutical Field

2016 ◽  
Vol 19 (1) ◽  
pp. 75-84
Author(s):  
Rayhan Hossain ◽  
Mohammad Arifur Rahman ◽  
Nargish Jahan Ara ◽  
AM Shafiqul Alam
Keyword(s):  
Waste Water ◽  
Low Cost ◽  
Animal Health ◽  
Oxygen Demand ◽  
Free Water ◽  
Second Order ◽  
Batch Adsorption ◽  
High Concentration ◽  
Pseudo Second Order ◽  
Pharmaceutical Industries

The adsorption of levafix red (LR) dye from waste water via batch adsorption onto treated jute stick powder was investigated. Studies concerning the factors influencing the adsorption such as adsorbent dosage, pH, contact time and temperature were systematically investigated and discussed. The results revealed that the maximum removal of levafix red was ~91% from water. The kinetics data were analyzed using pseudo-first order and pseudo-second order models. It was best described by the pseudo-second order model. The adsorption equilibrium follows Langmuir isotherm. This result indicates that treated jute stick powder could be employed as low-cost alternatives to commercial activated carbon for the removal of levafix red (LR) from waste water. Rapid industrialization in Bangladesh has resulted in increased water pollution that has higher dye level. Waste water from dyeing and finishing factories is a significant source of environmental pollution. The waste water is typically characterized by high levels of COD (chemical oxygen demand) concentration, high concentration of coloring material, large amount of suspended solids, highly fluctuating pH and high temperature. Dyes may therefore present an ecotoxic hazard and introduces the potential danger of bioaccumulation that may eventually affect man by transport through the food chain. As pharmaceutical industries use lots of water and intake of this type of water might have adverse effects on human health. Therefore, water purification is extremely essential for human and animal health and dye free water may be farther purified for its proper use.Bangladesh Pharmaceutical Journal 19(1): 75-84, 2016

scholarly journals Effect of Nonlinear Baseline Length Constraint on Global Navigation Satellite System Compass: A Theoretical Analysis

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Yanlong Chen ◽  
Jincheng Fan ◽  
Guobin Chang ◽  
Siyu Zhang
Keyword(s):  
Global Navigation Satellite System ◽  
Low Cost ◽  
Satellite System ◽  
Baseline Length ◽  
Navigation Satellite ◽  
Angle Estimation ◽  
Length Constraint ◽  
Simple Scaling ◽  
Global Navigation ◽  
Global Navigation Satellite

GNSS (global navigation satellite system) compass is a low-cost, high-precision, and temporally stable north-finding technique. While the nonlinear baseline length constraint is widely known to be important in ambiguity resolution of GNSS compass, its direct effect on yaw angle estimation is theoretically analyzed in this work. Four different methods are considered with different ways in which the length constraint is made use of as follows: one without considering the constraints, one with simple scaling, one with indirect statistical scaling, and one with direct statistical scaling. It is found that simple scaling does not have any effect on yaw estimation; indirect and direct statistical scalings are equivalent to each other with both being able to increase the precision. The analysis and the conclusion developed in this work can go in parallel for the case of the tilt angle estimation.

scholarly journals Simultaneous production of DHA and squalene from Aurantiochytrium sp. grown on forest biomass hydrolysates

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Alok Patel ◽  
Ulrika Rova ◽  
Paul Christakopoulos ◽  
Leonidas Matsakas
Keyword(s):  
Low Cost ◽  
Forest Biomass ◽  
Dry Weight ◽  
Scale Production ◽  
Simultaneous Generation ◽  
Nutraceutical Compounds ◽  
Lignocellulosic Feedstock ◽  
Oleaginous Microorganism ◽  
Wide Range ◽  
Pharmaceutical Industries

Abstract Background Recent evidence points to the nutritional importance of docosahexaenoic acid (DHA) in the human diet. Thraustochytrids are heterotrophic marine oleaginous microorganisms capable of synthesizing high amounts of DHA, as well as other nutraceutical compounds such as squalene, in their cellular compartment. Squalene is a natural triterpene and an important biosynthetic precursor to all human steroids. It has a wide range of applications in the cosmetic and pharmaceutical industries, with benefits that include boosting immunity and antioxidant activity. Apart from its nutritional quality, it can also be utilized for high-grade bio-jet fuel by catalytic conversion. Results In the present study, the potential of thraustochytrid strain Aurantiochytrium sp. T66 to produce DHA and squalene was evaluated. When the strain was cultivated on organosolv-pretreated birch hydrolysate (30 g/L glucose) in flask, it resulted in 10.39 g/L of cell dry weight and 4.98 g/L of total lipids, of which 25.98% was DHA. In contrast, when the strain was grown in a bioreactor, cell dry weight, total lipid, and DHA increased to 11.24 g/L, 5.90 g/L, and 35.76%, respectively. The maximum squalene yield was 69.31 mg/gCDW (0.72 g/L) when the strain was cultivated in flask, but it increased to 88.47 mg/gCDW (1.0 g/L), when cultivation shifted to a bioreactor. Conclusions This is the first report demonstrating the utilization of low cost non-edible lignocellulosic feedstock to cultivate the marine oleaginous microorganism Aurantiochytrium sp. for the production of nutraceutical vital compounds. Owing to the simultaneous generation of DHA and squalene, the strain is suitable for industrial-scale production of nutraceuticals.

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