Photobioreactors: Design and performance with respect to light energy input

Author(s):  
Otto Pulz ◽  
Karl Scheibenbogen
2019 ◽  
Vol 12 (2) ◽  
pp. 49-57
Author(s):  
Muhammad Iqbal Abdi Lubis ◽  
Renny Eka Putri ◽  
Ashadi Hasan ◽  
Feri Arlius ◽  
Santosa Santosa

Abstrak. Teknik penyemprotan adalah salah satu aktivitas yang berperan dalam mengoptimalkan pertumbuhan padi. Penyemprotan dilaksanakan petani untuk melindungi padi dari hama, penyakit, dan juga untuk menstimulasi pertumbuhan padi dan biasanya dilakukan pada 15 HST. Selama kegiatan produksi pertanian, energi input selama kegiatan berlangsung dapat diketahui berdasarkan beberapa parameter energi. Beberapa input energi yang dievaluasi pada aktivitas penyemprotan adalah energi pestisida dan energi operator (manusia). Tujuan dari penelitian ini mengevaluasi energi dari aktivitas penyemprotan, analisis teknis kerja, dan membandingkan energi manusia yang dihitung dengan alat (Garmin forerunner 35) dan faktor konversi. Aktivitas penyemprotan pada penelitian ini dianalisis pada 5 petak sawah pada 15 HST. Total pestisida yang digunakan dan rata-rata energi pestisida adalah 0,3419 kg/ha dan 67,6612 MJ/ha. Pada saat penyemprotan operator menggunakan knapsack manual (kap. 16 liter). Kapasitas kerja efektif untuk penyemprotan adalah 51,9759 l/ha. Energi operator yang dihitung menggunakan alat dan faktor konversi adalah 5,2480 dan 2,4243 MJ/ha. Hal ini menunjukkan bahwa energi terbesar pada aktivitas penyemprotan terdapat pada energi pestisida dan yang paling kecil adalah energi manusia.Energy and Performance Evaluation on Spraying Activity Paddy in Sumatera BaratAbstract. Spraying technique is one of the activities in optimize the growth of rice plants. Spraying is doing by farmers to protecting paddy from pest, disease, and also to stimulate growth up of the paddy usually since paddy at 15 DAP. In the process of agricultural production, input production facilities can be assessed as an energy parameter. Some energy input which evaluating in spraying activities are pesticides and labor energy. The objectives of this study are evaluated energy of spraying activity, analyzed technical performance, and compared between labor energy analyzed by tools (Garmin forerunner 35) and conversion factor. The spraying activity in this study has analyzed on five plots of the paddy field at 15 DAP. The results showed 0.3419 kg/ha and 67.6612 MJ/ha for pesticides used and the average of pesticide energy. respectively. For spraying activity, the labor used manual knapsack (cap. 16 liters). The effective work capacity for spraying is 51.9759 l/h. The labor energy which calculated by tools and conversion factor are 5.2480 and 2.4243 MJ/ha. It means which on spraying activity the largest input energy came from pesticides and the lowest one is labor energy.


Author(s):  
Z. Shao ◽  
M. Malobabic ◽  
D. Burhorn ◽  
M. Rautenberg

In recent years, an increasing awareness of the shortness of raw materials has led to an improved utilization of the energy input in thermal processes. Utilization of the heat generated in such processes and machinery can improve the overall efficiency of the latter and converse raw materials. In particular, combustion engines have a poor overall efficiency due to the high temperature exhaust gases which they produce. The classical Clausius-Rankine process can be applied to such machines in order to utilize the heat generated so as to provide turbocharging of the latter. The design of such a Clausius-Rankine process in connection with a newly-developed steam turbine based upon the Pelton principle is presented. In this design, particular value is placed upon the small size of individual units and a comparability with actual thermodynamic conditions in combustion engines.


1990 ◽  
Vol 112 (1) ◽  
pp. 100-106 ◽  
Author(s):  
Z. Shao ◽  
M. Malobabic ◽  
D. Burhorn ◽  
M. Rautenberg

In recent years, an increasing awareness of the shortness of raw materials has led to an improved utilization of the energy input in thermal processes. Utilization of the heat generated in such processes and machinery can improve the overall efficiency of the latter and converse raw materials. In particular, combustion engines have a poor overall efficiency due to the high-temperature exhaust gases they produce. The classical Clausius-Rankine process can be applied to such machines in order to utilize the heat generated so as to provide turbocharging of the latter. The design of such a Clausius-Rankine process in connection with a newly developed steam turbine based upon the Pelton principle is presented. In this design, particular value is placed upon the small size of individual units and a comparability with actual thermodynamic conditions in combustion engines.


2008 ◽  
Vol 159 (6) ◽  
pp. 140-145 ◽  
Author(s):  
Werner Grosse ◽  
Dirk Landgraf ◽  
Volkhard Scholz ◽  
Joachim Brummack

Short-rotation plantations are harvested in cycles of three to twenty years, depending on the production aim. In contrast to the establishment and recultivation costs, the costs for harvesting and processing of the wood occur regularly. The harvesting technology should be chosen with respect to the desired outcome – logs or chips. This is crucial for the process costs as well as the possible performance. A combination of forestry harvesters and forwarders is recommended when logs will be harvested. If the wood will be used energetically, an agricultural combined harvester and chipper fitted with suitable harvesting aggregates is the best technology with respect to productivity and performance, as well as for economic reasons. For drying the wood chips, an air ventilation process based on the self-heating of freshly harvested wood chips is an effective method for drying the wood without external energy input. With this method, it is possible to reduce the water content to 30% within three months.


2021 ◽  
Vol 188 (5) ◽  
Author(s):  
Arne Behrent ◽  
Christian Griesche ◽  
Paul Sippel ◽  
Antje J. Baeumner

AbstractLaser-induced graphene (LIG) has emerged as a promising electrode material for electrochemical point-of-care diagnostics. LIG offers a large specific surface area and excellent electron transfer at low-cost in a binder-free and rapid fabrication process that lends itself well to mass production outside of the cleanroom. Various LIG micromorphologies can be generated when altering the energy input parameters, and it was investigated here which impact this has on their electroanalytical characteristics and performance. Energy input is well controlled by the laser power, scribing speed, and laser pulse density. Once the threshold of required energy input is reached a broad spectrum of conditions leads to LIG with micromorphologies ranging from delicate irregular brush structures obtained at fast, high energy input, to smoother and more wall like albeit still porous materials. Only a fraction of these LIG structures provided high conductance which is required for appropriate electroanalytical performance. Here, it was found that low, frequent energy input provided the best electroanalytical material, i.e., low levels of power and speed in combination with high spatial pulse density. For example, the sensitivity for the reduction of K3[Fe(CN)6] was increased almost 2-fold by changing fabrication parameters from 60% power and 100% speed to 1% power and 10% speed. These general findings can be translated to any LIG fabrication process independent of devices used. The simple fabrication process of LIG electrodes, their good electroanalytical performance as demonstrated here with a variety of (bio)analytically relevant molecules including ascorbic acid, dopamine, uric acid, p-nitrophenol, and paracetamol, and possible application to biological samples make them ideal and inexpensive transducers for electrochemical (bio)sensors, with the potential to replace the screen-printed systems currently dominating in on-site sensors used. Graphical abstract


Author(s):  
H. M. Thieringer

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.


Author(s):  
Huang Min ◽  
P.S. Flora ◽  
C.J. Harland ◽  
J.A. Venables

A cylindrical mirror analyser (CMA) has been built with a parallel recording detection system. It is being used for angular resolved electron spectroscopy (ARES) within a SEM. The CMA has been optimised for imaging applications; the inner cylinder contains a magnetically focused and scanned, 30kV, SEM electron-optical column. The CMA has a large inner radius (50.8mm) and a large collection solid angle (Ω > 1sterad). An energy resolution (ΔE/E) of 1-2% has been achieved. The design and performance of the combination SEM/CMA instrument has been described previously and the CMA and detector system has been used for low voltage electron spectroscopy. Here we discuss the use of the CMA for ARES and present some preliminary results.The CMA has been designed for an axis-to-ring focus and uses an annular type detector. This detector consists of a channel-plate/YAG/mirror assembly which is optically coupled to either a photomultiplier for spectroscopy or a TV camera for parallel detection.


Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.


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