One-pot Synthesis of Substituted Pyrroles with N,N,N’,N’-Tetrachlorobenzene-1,3-disulphonamide and N,N’-Diiodo-N,N’-1,2-ethanediylbis(p-toluenesulphonamide) as Novel Catalytic Reagents

In this research, N,N,N’N’-tetrachlorobenzene-1,3-disulphonamide as novel catalytic reagent and N,N’-diiodo-N,N’-1,2-ethanediylbis(p-toluenesulphonamide) as new catalyst were used for the synthesis of N-substituted pyrroles in good to excellent yields under mild conditions. These reusable reagents were compared with existing reagents and it is clear that this study is a welcome addition in the field of pyrrole synthesis.Keywords: Pyrroles, Paal-Knorr reaction, TCBDA, NIBTS, catalytic reagen

Comparison of survival and larvae physiological resistance of white shrimp, Litopenaeus vannamei, fed with live food (rotifer and Artemia urmiana) and concentrated food

Anemia nauplii and rotifier are considered as the most important live food in aquaculture because of their high nutritional quality, suitable size and mobility. The survival rate and resistance of white shrimp (Litopenaus vannamei) postlarvae fed by Artemia urmiana, Brachinus plicatilis and concentrated food were investigated. Larvae at the stage of Protozoae 1 were stocked in 14 liters plastic containers filled by 6 liters of water. There were 75 larvae per liter in each container. The larvae were fed in 3 treatments: T1 (rotifier), T2 (Artemia) and T3 (concentrated food). Each treatment was repeated 3 times and used during Protozoae 1 (PLC} to Post-larvae 5 (PLO stages. Data analysis was done through Duncan Test. We observed that from Mysis 1 stage to PL1 the rotifier can be used for shrimp feeding and from this stage to PL5, Artemia nauplii can be used as food for the larvae. To evaluate the quality of larvae, the physiological resistance tests were conducted against formalin and salinity in different periods of time (30, 60 and 90 minutes). We found that at the PLC stage, the maximum survival (100%) in formalin tests (I 0Oppm) and (200ppm) and salinity test (15ppt) was related to feeding the shrimp larvae with rotifier. However, at the PL5 stage, the maximum survival (100%) under the same conditions was related to application of Artemia nauplii food. The concentrated food showed the minimum survival in all tests

A Review Paper on Comparison of Numerical Techniques for Finding Approximate Solutions to Boundary Value Problems on Post-Buckling in Functionally Graded Materials

The use of finite element models as research tools in biomechanics and orthopedics grew exponentially over the last two decades. However, the attention to mesh quality, model validation and appropriate energy balance methods and the reporting of these metrics has not kept pace with the general use of finite element modeling. Therefore, the purpose of this review was to develop the nonlinear filter and thermal buckling of an FGM panel under the combined effect of elevated temperature conditions and aerodynamic loading is investigated using a finite element model based on the thin plate theory and von Karman strain-displacement relations to account for moderately large deflection. It is found that the temperature increase has an adverse effect on the FGM panel flutter characteristics through decreasing the critical dynamic pressure. Decreasing the volume fraction enhances flutter characteristics, but this is limited by the structural integrity aspect. Structural finite element analysis has been employed to determine the FGM panel's adaptive response while under the influence of a uniaxial compressive load in excess of its critical buckling value. By increasing the applications of using composite materials inside aviation stages, it is visualized that the versatile FGM plate setup will broaden the operational execution over traditional materials and structures, especially when the structure is presented to a raised temperature. The vicinity of air motion facilitating stream brings about delaying the locking temperature and in stifling under loads, while the temperature build gives route for higher thermal-cycle abundance

Solvent-free Oxidation of Alcohols and Mild Catalytic Deprotection of Silyl Ethers with Poly(N,N’-dibromo-N-ethyl-benzene-1,3-disulphonamide) and N,N,N’,N’-tetrabromobenzene-1,3-disulphonamide

Poly(N,N’-dibromo-N-ethyl-benzene-1,3-disulphonamide) (PBBS) and N,N,N’,N’-tetrabromobenzene- 1,3-disulphonamide (TBBDA) can be used for solvent-free oxidation of primary and secondary alcohols to the corresponding carbonyl compounds without over-oxidation, and efficient catalytic deprotection of various silyl ethers to hydroxyl groups in aprotic organic solvents under ambient conditions.KEYWORDS: Solvent-free oxidation, alcohols, catalytic deprotection, silyl ethers, PBBS, TBBDA

Deep Attention Models for Human Tracking Using RGBD

Visual tracking performance has long been limited by the lack of better appearance models. These models fail either where they tend to change rapidly, like in motion-based tracking, or where accurate information of the object may not be available, like in color camouflage (where background and foreground colors are similar). This paper proposes a robust, adaptive appearance model which works accurately in situations of color camouflage, even in the presence of complex natural objects. The proposed model includes depth as an additional feature in a hierarchical modular neural framework for online object tracking. The model adapts to the confusing appearance by identifying the stable property of depth between the target and the surrounding object(s). The depth complements the existing RGB features in scenarios when RGB features fail to adapt, hence becoming unstable over a long duration of time. The parameters of the model are learned efficiently in the Deep network, which consists of three modules: (1) The spatial attention layer, which discards the majority of the background by selecting a region containing the object of interest; (2) the appearance attention layer, which extracts appearance and spatial information about the tracked object; and (3) the state estimation layer, which enables the framework to predict future object appearance and location. Three different models were trained and tested to analyze the effect of depth along with RGB information. Also, a model is proposed to utilize only depth as a standalone input for tracking purposes. The proposed models were also evaluated in real-time using KinectV2 and showed very promising results. The results of our proposed network structures and their comparison with the state-of-the-art RGB tracking model demonstrate that adding depth significantly improves the accuracy of tracking in a more challenging environment (i.e., cluttered and camouflaged environments). Furthermore, the results of depth-based models showed that depth data can provide enough information for accurate tracking, even without RGB information

Comparative study of the effects of HUFA in dry diets and natural foods on fecundity and egg diameter of female broodstock of white leg shrimp (Litopenaeus vannamei)

During 2 months (from April to June, 2008) we studied the suitable quantity of Highly Unsaturated Fatty Acids (HUFA) for desirable fecundity and egg diameter of female broodstock of white leg shrimp (Litopenaeus vannamei). Similar dry food containing Isonitrogeneous material (31.5% protein) and Isolipid (6.9% lipid) was used but with different levels of HUFA (1, 2 and 3%). Also, the HUFA of natural foods (Perinereis worm, melalis bivalvia and cuttlefish) was analyzed. We compared the effects of four levels of dietary HUFA (1, 2 & 3 % HUFA of dry diets and the average HUFA of natural diets) on fecundity and egg diameter of female broodstock of white leg shrimp. The fecundity and egg diameter of natural diet and HUFA 3% were not significantly different (P>0.05). The fecundity of natural diet and HUFA 3% was significantly higher than the other two treatments (P<0.05) and also the egg diameter of HUFA 3% and natural diet was significantly higher than the other two treatments (P<0.05). According to the results of fecundity and egg diameter measurements, both natural and HUFA 3% diets are suggested as suitable for white leg shrimp breeding

Evaluate performance of precast concrete wall to wall connection

The building industry keeps growing towards industrialization in construction by implementing Industrialized Building System (IBS). The components of IBS Structure which are floors, walls, columns, beams and roofs are assembled and erected on the site by properly joints to form the final units. The present study deals with the evaluation of precast wall connections subjected to inplane lateral ground movement. For this purpose, 3D finite element model of precast walls and connection is developed using finite element model. The interaction between casting concrete and precast concrete as well as reinforcements and concrete is modelled with nonlinear stress-strain behavior, to consider the yielding of steel and concrete. The model was subjected to lateral ground movement and the performance of connection is evaluated in terms of the stress, deformation and absolute plastic strain

Development of constitutive model for precast prestressed concrete segmental columns

The interest of using precast segmental columns in construction of concrete bridges has significantly increased in recent years. One research area of concrete bridges is the application of Precast Prestressed Concrete Segmental (PPCS) Column in any structural analysis software or FE program code. Modeling a PPCS column, which consists of various materials with interaction between them, is complicated and time-consuming. This research attempts to formulate the stiffness matrix of PPCS columns in order to form the constitutive model in linear form to evaluate the response of the columns. A two-dimensional finite element model is presented in the finite element package ANSYS. Parametric studies are conducted by finite element models to verify the constitutive models for the PPCS column with a different number of concrete segments. Comparison between the constitutive model and the FE program results indicates that the constitutive model is accurate enough to predict the deformation of the PPCS columns

New Precast Wall Connection Subjected to Rotational Loading

The connection of discrete elements in precast concrete structures has important role in overall continuity of the building. Investigations show that most precast structure damages occur in connections under earthquake loads or other disasters. This study aims to propose a new connection in order to improve rotational loading capacity and develop a finite element model of precast wall with connections by considering all details of different parts for a contemporary connection, as well as the proposed connection. Pushover analysis is conducted for major or minor bending moment and torsion moment degrees of freedom (DOFs) to obtain the capacity of each type of connection. Four key features of concrete panels and steel reinforcements are considered to determine the effect of incremental lateral movements. Pushover results indicate a significant improvement in the maximum flexural strength of the proposed connection. Indeed, the maximum moment in the bending moment DOF is enhanced when the proposed connection is used. Consequently, the result reveals that the contemporary connection has a significant defect in terms of strength in bending moment and torsion moment DOFs

Development of a new connection for precast concrete walls subjected to cyclic loading

The Industrialized Building System (IBS) was recently introduced to minimize the time and cost of project construction. Accordingly, ensuring the integration of the connection of precast components in IBS structures is an important factor that ensures stability of buildings subjected to dynamic loads from earthquakes, vehicles, and machineries. However, structural engineers still lack knowledge on the proper connection and detailed joints of IBS structure construction. Therefore, this study proposes a special precast concrete wall-to-wall connection system for dynamic loads that resists multidirectional imposed loads and reduces vibration effects (PI2014701723). This system is designed to connect two adjacent precast wall panels by using two steel U-shaped channels (i.e., male and female joints). During casting, each joint is adapted for incorporation into a respective wall panel after considering the following conditions: one side of the steel channel opens into the thickness face of the panel; a U-shaped rubber is implemented between the two channels to dissipate the vibration effect; and bolts and nuts are used to create an extension between the two U-shaped male and female steel channels. The developed finite element model of the precast wall is subjected to cyclic loads to evaluate the performance of the proposed connection during an imposed dynamic load. Connection performance is then compared with conventional connections based on the energy dissipation, stress, deformation, and concrete damage in the plastic range. The proposed precast connection is capable of exceeding the energy absorption of precast walls subjected to dynamic load, thereby improving its resistance behavior in all principal directions