With the use of ab initio X-ray powder diffraction, a family of isostructural crystalline porous coordination networks, [(ZnX(2))(3)(TPT)(2)](n)· (solvent) (X = I, Br, Cl), has been studied at elevated temperatures of 573-723 K. Upon heating, all three networks exhibited crystalline-to-amorphous-to-crystalline (CAC) phase transformations to three new networks, [(ZnI(2))(3)(TPT)(2)](n), [(ZnBr(2))(3)(TPT)(2)](n)·(H(2)O) and [(ZnBr(2))(μ-Br)(ZnBr)(TPT)](n), and [(ZnCl(2))(μ-Cl)(ZnCl)(TPT)](n), respectively. A set of control experiments was used to obtain detailed mechanistic aspects of the CAC transformations. We demonstrate how bonds are broken and formed in these significant molecular rearrangements and how the initial arrangement plays a crucial role in the formation of the new networks after the CAC transformations. The structural information in the amorphous phase is retained and passed from a metastable to a more stable crystal, thus, reinforcing the notion that coordination networks are flexible and chemically active.

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Cryptography is the study that provides security service. It concerns with confidentiality, integrity, and authentication. Public key cryptography provides an enormous revolution in the field of the cryptosystem. It uses two different keys where keys are related in such a way that, the public key can use to encrypt the message and private key can be used to decrypt the message. This paper proposed an enhanced and modified approach of RSA cryptosystem based on "n" distinct prime number. This existence of "n" prime number increases the difficulty of the factoring of the variable "N" which increases the complexity of the algorithm. In this approach, two different public key and private key generated from the large factor of the variable "N" and perform a double encryption-decryption operation which affords more security. Experiment on a set of a random number provided that the key generation time, analysis of variable "N", encryption and decryption will take a long time compared to traditional RSA. Thus, this approach is more efficient, highly secured and not easily breakable.

Abstract-The Wireless Sensor Network (WSN) is made up with small batteries powered sensor devices with limited energy resources within it. These sensor nodes are used to monitor physical or environmental conditions and to pass their data through the wireless network to the main location. One of the crucial issues in wireless sensor network is to create a more energy efficient system. Clustering is one kind of mechanism in Wireless Sensor Networks to prolong the network lifetime and to reduce network energy consumption. In this paper, we propose a new routing protocol called Fuzzy Based Energy Efficient Multiple Cluster Head Selection Routing Protocol (FEMCHRP) for Wireless Sensor Network. The routing process involves the Clustering of nodes and the selection of Cluster Head (CH) nodes of these clusters which sends all the information to the Cluster Head Leader (CHL). After that, the cluster head leaders send aggregated data to the Base Station (BS). The selection of cluster heads and cluster head leaders is performed by using fuzzy logic and the data transmission process is performed by shortest energy path which is selected applying Dijkstra Algorithm. The simulation results of this research are compared with other protocols BCDCP, CELRP and ECHERP to evaluate the performance of the proposed routing protocol. The evaluation concludes that the proposed routing protocol is better in prolonging network lifetime and balancing energy consumption.

S3 is one of the basic allotropes of sulfur but is still a mysterious labile species. We selectively trapped S3 in a pore of a thermally stable coordination network and determined S3 structure by ab initio X-ray powder diffraction analysis. S3 in a pore has a C2v bent structure. The network containing trapped S3 is remarkably stable under ambient conditions and is inert to photoirradiation. S3 in the network could be transformed to S6 by mechanical grinding or heating in the presence of NH4X (X = Cl or Br). S6 could be reverse-transformed to S3 by photoirradiation. We also determined the structure of the network containing S6 by ab initio X-ray powder diffraction analysis.

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Synchrotron powder XRD analysis was used to solve the crystal structure of a kinetically controlled coordination network including tetrathiafulvalene (TTF) guests, which has a large unit cell (15 729(1) Å3). Very short S⋅⋅⋅S contacts among the TTF guests were achieved by confinement in the network pores (see picture).

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