In this paper, recommended spiral passive micromixer was designed and simulated. spiral design has the potential to create and strengthen the centrifugal force and the secondary flow. A series of simulations were carried out to evaluate the effects of channel width, channel depth, the gap between loops, and flowrate on the micromixer performance. These features impact the contact area of the two fluids and ultimately lead to an increment in the quality of the mixture. In this study, for the flow rate of 25 μl/min and molecular diffusion coefficient of 1×10-10 m2/s, mixing efficiency of more than 90% is achieved after 30 (approximately one-third of the total channel length). Finally, the optimized design fabricated using proposed 3D printing method.

Application of the network equivalent concept for external system representation for power system transient analysis is well known. However, the challenge to utilize an equivalent network, approximated by a rational function, is to guarantee the passivity of the corresponding model. In this regard, special techniques are required to enforce the passivity of the equivalent model through a post processing approach that minimizes its impact on the original model characteristics. In this paper, the passivity is enforced by expressing the problem in terms of a convex optimization problem that guarantees the global optimal solution. The convex optimization problem is efficiently solved by recently developed numerical interior–point methods. This passivity enforcement is also global which indicates that the passivity enforcement in one region does not lead to passivity violation in other regions.

Introduction: Arabidopsis thaliana (Arabidopsis thaliana) is the most important model plant in plant nutrition studies, genetics, and plant biotechnology. Arabidopsis cultivation is mainly done in either soil or soilless systems. Soil cultivation of Arabidopsis in compared to soilless culture does not have precise control on the concentration and ratio of mineral elements in the substrate, salinity, and pH, which results in negative effects on plant growth, biochemical reactions, etc. However, soilless or hydroponic systems due to the exact control of plant nutritional needs and the substrate are more compatible for high accuracy experiments such as plant nutrition, especially for primary seedling growth. Accordingly, this experiment was conducted to provide an optimized Arabidopsis Germination system for production of healthy seedlings for soilless systems based on the agar-nutrient media. Materials and Methods: This experiment was conducted based on the importance of the development of Arabidopsis in soilless systems in order to provide accurate nutritional and physiological trials and the importance of effective Germination and the production of healthy seedlings in an agar-nutrient media. Therefore, two milliliters microtubes were cut into 10 mm in length, and connected upsidedown to the table with adhesive tape then were filled with agar (0. 55%) and mineral elements (Hoagland formulation) medium. (1: 1 V/V). Sterilized and stratified Arabidopsis seeds were sown on filled microtubes and then transferred to the growth chamber with controlled environmental conditions. Germination percentage and growth and development parameters of seedlings were measured for three weeks. Results and discussion: Results showed the effectiveness of the optimized Germination system and also the agar-nutrient medium for Arabidopsis. Accordingly, seed Germination percentage was more than 97. 5%. Also, production of healthy seedlings with optimum growth (85%) especially the production of intact roots for various biological root and nutritional studies was another advantage of this experiment. Based on the results three weeks old plants were ready for transplanting to the main cultivation system. Conclusion: The results of the present study led to the conclusion that optimized system and medium due to high efficiency, simple and possible design, precise control of the substrate and root medium, could be recommended for Arabidopsis Germination experiments and also arabidopsis cultivation for nutritional purposes.

Ephedra is a dioecious shrub belongs to the Ephedraceae family. Almost all commercial applications of Ephedra extracts is derived from the ephedrine alkaloids found in the evergreen stems. The purpose of this study was to investigate seed Germination in green house condition and total alkaloid and ephedrine amounts measurement. The Ephedra seeds were collected from Bojnoord region and germinated on the wet paper and MS medium under control and cold treatment conditions. The results revealed that cold treatment did not show any significant effect on seed Germination. To determine optimum condition for Ephedra seed Germination, another experiment was performed in complete randomized design with 6 different medium culture (forest soil, Bojnoord soil, a mixture of forest and Bojnoord soil, coco peat, compost and sand) and 4 replicates. The obtained results showed that the maximum (90%) and minimum (8%) percent of seed Germination was observed on forest soil and compost medium, respectively. Meanwhile the highest dry and fresh weight of shoot and root was obtained in plantlets that were grown on forest soil. On other hands, total alkaloid level in the stem organ plants that were grown on forest soil was 1.04 mg/g dry weight, but in root organ it was 0.04 mg/g dry weight. Data from HPLC analysis revealed that while root is depleted of ephedrine, the ephedrine amount in stem organ is 0.04 mg/g dry weight.

Temperate fruits including small fruits, especially Strawberries are important fruit crops which mostly for fruit set needs the pollination of flowers and followed by pistil fertilization. Therefore, to achieve this act, pollen viability and its Germination capability are essential. Examination of pollen viability and understand its quality is important. To optimize the pollen Germination medium of Strawberry, an experimental was carried out with 9 types of culture medium containing different concentrations of boric acid (0, 25 and 50 mgL-1), sucrose (7.5, 10 and 15 %) and agar (2 %) in the In-vitro using random complete design with three replications. The results showed that maximum Germination in combination medium B25S15 (25 mg boric acid and 15 % sucrose) with 87.66% Germination was lowest Germination medium in combination B0S7.5 (0 mg boric acid and 7.5 % sucrose) with 5.33% Germination occurred. The viability of pollen Strawberry two months after maintenance at temperatures -20oC and -80oC showed that pollen stored at temperatures above maintain viability of pollen Germination or no significant difference. Also, the results from pollen Germination in selected culture medium showed that maximum pollen Germination (83.93%) in laboratory condition was obtained and lowest pollen Germination percentage in 10oC with 51.66 % occurred.

The effects of the physical factors on dielectric characteristics of wheat biological parts were studied. Due to the sensitivity of phytochromes to the red light, the activity of the related enzymes as well as the inner energy and seed entropy during Germination can be increased through irradiation He-Ne laser light to the plant seed with the wave length of 623nm, which, in turn, leads to the increased energy exchange between the seed and the environment. In this research, wheat varieties as Shiroudi, Zagros, Tajan and Kouhdasht were used under the He-Ne laser (623nm, 0.1 mW/mm-2) in time periods of 10, 15, 20, 25 and 30 minutes. Moreover, in order to investigation the radial effects of laser on the traits of the rootlet and the stemlet length on the fresh weight of stemlet and rootlet, number of seedlings, drought weight of stemlet and rootlet, and seed Germination, four cultivars of wheat in five replication with factorial experiment as completely randomized design (CRD) have been studied. The results indicated that Zagros variety and Shiroudi variety had the fastest rate of seed Germination, with 0.942(N/d) and 0.910(N/d), respectively. The result of this research indicates that cultivar Zagros with 0.006(grf), had he highest drought weight of rootlet among the cultivars. Also results showed that cultivar Zagros had more growth and drought weight of stemlet among the cultivars.

One of the technologies used to improve seed Germination is use of cold plasma. Cold plasma is created at atmospheric pressure or vacuum by using electrical discharge in low pressure gas. In order to investigate the effect of two cold plasma production systems on improving the Germination indices of chickpea seeds from Adel, Mansour and Azad cultivars in three plasma exposure times of 0, 30 and 60 seconds, they were studied in a completely randomized factorial design. The results showed that cold plasma treatment by corona method at 30 seconds exposure caused a significant increase in the root length index compared to the control treatment in Adel and Mansur varieties. Also, cold plasma treatment by corona method in 30 seconds of exposure caused improvement in seed vigor in Adel and Mansour varieties, respectively, by 35% and 41% compared to the control and root length in 30 seconds corona treatment in Adel Mansur and Azad varieties, respectively increased by 38%, 42% and 2% compared to the control. On the other hand, in the barrier method, only in the root length index, in Azad variety and in exposure to cold plasma for 60 seconds, 25% increase was observed compared to the control. Therefore a significant positive effect on increasing seed vigor and root length of chickpea varieties tested in cold plasma treatment by corona method compared to the control, while the barrier dielectric method has more uniformity in the treatments than corona method.

In this study, the effect of ultrasound on the Germination and vigor index of Iranian black cumin (Bunium persicum Boiss.), was studied. Response surface methodologhy and central composite design were used ti analyze the data and optimize the experiment. A factorial experiment based on completely randomized design was conducted. Experimental factors included time of ultrasound treatment (5, 7 and 9 minutes), ultrasonic power (130, 180 and 230 watts) and sonication temperatures (10, 20 and 30 °C) as well as control and Germination percentage and seed vigor index were measured. The highest Germination percentage and seed vigor index were determined by Response Surface Methodology (RSM). The results indicated significant effect of time and ultrasound power on studied traits, but temperature had no significant effect on them. The highest Germination percentage (61%) and seed vigor index (800) were observed at 180 W and 7 min duration time and 20 °C. The lowest Germination percentage (24.5%) and seed vigor index (462) were observed in 230 W ultrasound power, 9 min duration time and 20 °C. Also, the optimization results showed that the best points for power, time and temperature for achieving the highest values of Germination percentage and seed vigor index were 175.47 W, 6.37 min and 19.36 °C, respectively and the output values (Germination and seed vigor index) were obtained the this points 63.02% and 808.39 respectively. Finally it seems that the increasing or decreasing time and power of ultrasonication in a certain range decreases the seed Germination percentage and vigor index.