Design and fabrication of a microfluidic device for synthesis of chitosan nanoparticles

Cataloged from PDF version of article.Chitosan nanoparticles have a biodegradable, biocompatible, nontoxic structure, and are commonly used for drug delivery systems. In this study, design, modeling, and fabrication methodology of a microfluidic device for the synthesis of chitosan nanoparticles is presented. In the modeling, 2D flow and concentration field is computed using COMSOL Multiphysics® simulation environment to predict the performance of the device. The microfluidic chip is fabricated out of PDMS. The fabrication of the mold for the microfluidic device is performed using high-precision micromachining. Some preliminary proof-of-concept experiments were performed. It was observed that compared to conventional batch-type methods, the proposed microfluidic device can perform the synthesis much faster and in a much automated and convenient manner. Copyright © 2013 by ASME

Behaviour of laminated circular glass plates

Laminated circular glass plates consist of two or more thin glass plates and an interlayer PVB (PolyVinyl Butyral), and are widely used geometric types in modern structures. They can easily undergo large displacements since they are very thin. Their behaviour under large displacements has shown a highly nonlinear characteristic. The mathematical model needs to be developed to simulate this behaviour. The energy integral functional is written for the whole unit, and variations are taken with respect to lateral displacement and radial displacement to obtain the governing differential equations. Then, the nonlinear coupled differential equations are converted to the system of nonlinear algebraic equations by the use of finite difference approach

Modelling alicyclobacillus acidoterrestris inactivation in apple juice using thermosonication treatments

A spore-forming bacterium, Alicyclobacillus acidoterrestris, is often responsible for fruit juices quality degradation. The objective was to study the influence of ultrasounds and combinations with temperature (thermosonication) on A. acidoterrestris spores inactivation in apple juices. Commercially available juice was artificially inoculated with the bacterium (∼105 CFU/mL). Sonication was carried out in an ultrasonic bath (35 kHz; 120–480 W) at room temperature and at 70, 80, 85, 90 and 95 °C for different times. Thermal treatments at the same temperatures were performed as a control. Sonication had no significant effect on A. acidoterrestris spores inactivation. However, when applied at 70 and 80 °C, it allowed 1 log-cycle more of inactivation when compared to thermal treatments and at the end of the processes. Ultrasounds at higher temperatures required approximately half of the treatment time to attain the same inactivation that occurred when the thermal processes were applied alone. In thermosonicated juices, spores decreased by 4.8, 4.7 and 5.5 log-cycles (at 85, 90 and 95 °C, respectively) after 90, 60 and 20 min. The Weibull model satisfactorily fitted inactivation data of thermosonicated juices. Thermosonication is efficient for A. acidoterrestris spores inactivation, with a drastic impact on spores’ loads when high temperatures are used.info:eu-repo/semantics/acceptedVersio

2-(4-Bromo­phen­yl)-2-oxoethyl anthracene-9-carboxyl­ate

In the title compound, C23H15BrO3, the anthracene ring system is essentially planar [maximum deviation = 0.29 (2) Å] and makes a dihedral angle of 5.74 (8)° with the mean plane of the bromo-substituted benzene ring. An intra­molecular C—H⋯O hydrogen bond generates an S(9) ring motif. In the crystal, mol­ecules are linked by C—H⋯O inter­actions, forming a two-dimensional network parallel to the ac plane. π–π stacking inter­actions are observed between benzene rings [centroid–centroid distances = 3.5949 (14) and 3.5960 (13) Å]

4-(o-Tol­yl)piperazin-1-ium chloride

In the title mol­ecular salt, C11H17N2 +·Cl−, the piperazin-1-ium ring adopts a chair conformation with the aromatic ring in a pseudo-equatorial orientation. The dihedral angle between the benzene ring and the mean plane of the piperazin-1-ium ring is 51.22 (6)°. In the crystal, N—H⋯Cl hydrogen bonds link the mol­ecules into chains propagating in [100]. Weak C—H⋯π inter­actions also ocur

4-(Morpholin-4-yl)-3-(trifluoro­meth­yl)­benzonitrile

In the title benzonitrile compound, C12H11F3N2O, an intra­molecular C—H⋯F hydrogen bond generates an S(7) ring motif. The trifluoro­methyl group is disordered over two orientations with a refined occupancy ratio of 0.549 (16):0.451 (16). The morpholine ring adopts a chair conformation. The benzene ring and mean plane of the morpholine ring make a dihedral angle of 58.04 (10)° with each other. In the crystal, mol­ecules are connected by inter­molecular C—H⋯F and C—H⋯O inter­actions to form R 2 2(8) ring motifs. These inter­actions also link the mol­ecules into chains parallel to the [10] direction

Pemanfaatan Damar oleh Masyarakat di Kampung Bariat Distrik Konda Kabupaten Sorong Selatan

Penelitian ini dilakukan kurang lebih 3 minggu pada 3 November sampai dengan 17 Nopember 2014 di Sorong Selatan. Tujuannya untuk mengidentifikasi pemanfaatan jenis tumbuhan damar oleh masyarakat lokal di kampung Bariat distrik Konda Kabupaten Sorong Selatan. Pengumpulan data dilakukan dengan pengamatan terlibat dan teknik wawancara dengan responden contoh adalah masyarakat lokal. Penelitian mencatat bahwa ada tiga kategori pemanfaatan damar yaitu getah (kopal), bahan bangunan dan digunakan sebagai bahan kayu bakar. Konservasi tradisional spesies ini oleh masyarakat lokal di Sorong Selatan dilakukan dengan menetapkan ketentuan pohon yang siap dipanen saja (Dbh > 50 cm dan tinggi > 4m). Terdapat pola konservasi pemanfaatan tradisional untuk pemungutan jenis damar putih (Agathis labilladeri Warb.) hanya boleh dilaksanakan oleh masyarakat lokal yang berasal dari marga Kemeray, Konjol, Sawor, dan, semetara jenis damar merah (Vatica sp.) dapat dipungut dan dimanfaatakan oleh seluruh marga pribumi dan masyarakat pendatang

2-(4-Chloro­phen­yl)-2-oxoethyl 2-meth­oxy­benzoate

In the title compound, C16H13ClO4, the two benzene rings make a dihedral angle of 86.38 (8)°. In the crystal, inter­molecular C—H⋯O hydrogen bonds link the mol­ecules to form columns along the a axis. The mol­ecules are also stabilized by a π–π stacking inter­action, with a centroid–centroid distance of 3.7793 (10) Å between the inversion-related benzene rings

4-(3-Chloro­phen­yl)-3-[(2,6-difluoro­benz­yl)sulfan­yl]-5-(3,4,5-trimeth­oxy­phen­yl)-4H-1,2,4-triazole

In the title compound, C24H20ClF2N3O3S, the essentially planar triazole ring (r.m.s. deviation = 0.001 Å) forms dihedral angles of 22.35 (10), 68.17 (10) and 42.01 (10)° with the mean planes of the trimeth­oxy­phenyl, chloro­phenyl and difluoro­phenyl rings, respectively. A weak intra­molecular C—H⋯π inter­action occurs. In the crystal, mol­ecules are linked into sheets lying parallel to the bc plane by C—H⋯O and C—H⋯N hydrogen bonds. The crystal packing also features weak C—H⋯π inter­actions