in this paper, design and construction of a tactile sensor for measuring contact-force is presented. mechanism of measuring contact-force in this tactile sensor is based on impedance changing of piezoelectric crystal and voltage of different points in circuit as a result of applying force on the crystal. by considering a specific point in the circuit and recording the changes of its voltage, ma...

In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. A crystal structure is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice. The spacing between unit cells in various directions is called its lattice parameters. The symmetry properties of the crystal are embodie...

Crystal engineering has recently emerged as a method of choice for the design and construction of organic as well as metal-organic functional materials. Crystal engineering attempts to establish packing trends in whole families of compounds and seeks to establish connections between structure and function. The utility of crystal engineering has also been expanded to the nanoscience and the deve...

the copper(ii) complex [cu(pic)2]·2h2o was synthesized with 2-picolinic acid (hpic) and copper acetate as reactants by room temperature solid-solid reaction. the composition and structure of the complex was characterized by elemental analyses, single crystal x-ray diffraction, x-ray powder diffraction, ft-ir spectroscopy and thermogravimetry-differential scanning calorimetry. the crystal struct...

the crystals of [ws (cuncs) ] anion have been isolated from ch ,ci solution and examined by x-ray structural analysis as well as by ir spectroscopy. the unit cell is monoclinic with a= 14.3796(13), b= 18.039(1 i), c= 22.5956(23)& p= 96.053(8)', space group p2,/n (14), z= 4. the crystal structure was refined by the least-squares calculations to a final r-value of 0.0398(rw= 0.0443) for 2777...

Calcium dichloride tetra urea was prepared by the reaction of calcium chloride with urea in aqueous solution. The crystals are monoclinic, a= 7.633, b= 12.45 1, c= 8.118 ?,? = 113.17, Z = 4, space group P 2,/a. The crystal structure was determined by single crystal X-ray methods and refined to R= 0.041. The calcium atoms are coordinated to four oxygen atoms of urea and to two chloride ions....