Crystals of Diphenyl-Benzothiadiazole and Its Derivative with Terminal Trimethylsilyl Substituents: Growth from Solutions, Structure, and Fluorescence Properties.

Linear conjugated molecules consisting of benzothiadiazole (BTD) and phenyl rings are highly efficient organic luminophores. Crystals based on these compounds have great potential for use as light-emitting elements, in particular, scintillation detectors. This paper compares the peculiarities of growth, structure, and fluorescent properties of crystals based on 4,7-diphenyl-2,1,3-benzothiadiazole () and its organosilicon derivative 4,7-bis(4-(trimethylsilyl)phenyl) BTD ().

A new linear phenyloxazole-benzothiadiazole luminophore: crystal growth, structure and fluorescence properties.

A new linear luminophore consisting of five conjugated units of oxazole, phenylene and a central benzothiadiazole fragment, 4,7-bis[4-(1,3-oxazol-5-yl)phenyl]-2,1,3-benzothiadiazole, has been synthesized and characterized. Needle-like single-crystal samples up to 10 mm in length were obtained by physical vapor transport. The crystal structure was determined at 95 K and 293 K using single-crystal X-ray diffraction.

Highly luminescent crystals of a novel linear π-conjugated thiophene-phenylene co-oligomer with a benzothiadiazole fragment.

The synthesis, growth from solutions and structure of crystals of a new linear thiophene-phenylene co-oligomer with a central benzothiadiazole fragment with a conjugated core, (TMS-2T-Ph)-BTD, are presented. Single-crystal samples in the form of needles with a length of up to 7 mm were grown and their crystal structure was determined at 85 K and 293 K using single-crystal X-ray diffraction. The conformational differences between the crystal structures are insignificant.

Highly Luminescent Solution-Grown Thiophene-Phenylene Co-Oligomer Single Crystals.

Thiophene-phenylene co-oligomers (TPCOs) are among the most promising materials for organic light emitting devices. Here we report on record high among TPCO single crystals photoluminescence quantum yield reaching 60%. The solution-grown crystals are stronger luminescent than the vapor-grown ones, in contrast to a common believe that the vapor-processed organic electronic materials show the highest performance.

Ultrasonography in patients without trauma in the emergency department: impact on discharge diagnosis.

Objective: The aim of this study was to examine to what extent findings on ultrasonography performed in the emergency department (ED) after hours confirm or alter the referral diagnosis in patients without trauma as reflected in the discharge diagnosis.

Methods: In this prospective study, data from 136 ultrasonographic examinations performed in patients without trauma after hours in the ED during January and February 2002 were evaluated against the suspected preimaging diagnosis of the referring ED physician and the actual discharge diagnosis from the ED or after hospitalization. The rate of preimaging and postimaging concordance was statistically analyzed and compared by calculation of confidence intervals and by the McNemar test.

Sonographic diagnosis of right segmental omental infarction.

Purpose: The purpose of this study was to identify the characteristic features of omental infarction so that this entity can be differentiated from other acute conditions in the right lower quadrant of the abdomen.

Methods: A retrospective review was undertaken. We searched our hospital medical records and found 6 patients with the diagnosis of omental infarction in the last 3 years.

[Oxidase activity of horseradish peroxidase in oxidation of the bilirubin-albumin complex].

The catalytic activity of horseradish peroxidase was investigated upon oxidation of the bilirubin-albumin complex (10(-5)-10(-4) M; BR: SA = 1: 1.5 mol/mol) by dissolved oxygen to biliverdin and other components. The process can be described by the Michaelis-Menten equation with Km = 14.

[Radiation control in roentgenologic studies].

A program named KODR (dosimetric monitoring of irradiation in radiodiagnosis) was developed for the SM-4 computer to ensure regional radiation monitoring. On the basis of statistical data on the distribution of x-ray studies the program made it possible to define collective effective equivalent doses and a mean value of an effective equivalent dose for one person in a given region.

[Analysis of errors in the determination of the collective equivalent dose in x-ray diagnostic studies].

The paper is devoted to an analysis of random errors in the determination of a collective effective equivalent dose resulting from radiodiagnostic investigations. The error of a collective dose does not exceed 30% and hardly depends on dose errors in human organs and tissues. The authors have established an extent of overestimation of the risk of long-term radiation effects in patients after x-ray investigations.

[Equivalent doses in x-ray studies].

The authors proposed a method of estimation of equivalent doses in x-ray investigations permitting the control of a possibility of the development of nonstochastic effects. They also considered a method for calculation of equivalent doses in x-ray investigations in the head and neck area and the rest of the patient's body.

[Radiation-health aspects of methods of x-ray study of the esophagus and stomach].

The authors considered technological chains of various methods of X-ray investigations of the upper part of the G.I. tract indicating the time of performance of each stage of investigation, equivalent and effective equivalent doses.

[Effect of the schedule of x-ray examinations on the radiation dosage of specific organs in patients].

It has been established on the basis of experimental dosimetric studies that during x-ray studies tissue doses of the irradiation of vital organs depend very little on the voltage of the x-ray tube in the range of 80-120 kV. It necessitates the use of x-ray radiation detectors with a high sensitivity as well as sparing technology of examination to decrease radiation exposure of patients. On condition of the constancy of tissue doses the main criterion for a chosen schedule is the informative value of an x-ray image.