Room temperature, solventless telomerization of isoprene with alcohols using (N-heterocyclic carbene)–palladium catalysts

The use of a custom-made palladium complex for the telomerisation of isoprene with alcohols under green conditions is described. Using a very low catalyst loading (0.1 mol%), this protocol allows for the reactions to be carried out without the need of high pressure equipment, at room temperature and under solventless conditions, affording high yields of telomerization products with high selectivity towards linear head-to-head and tail-to-head telomer

Оптимизация распределения температуры в ростовом объеме аппарата высокого давления типа «тороид»

Settlement methods define increase possibility growth volume of cells for single diamond crystals growing in toroid type high pressure equipment. It is shown that at volume increase of the growth cell on 25 % limiting values of temperature in characteristic points do not exceed the maximum values for this type equipment. It is shown that at growing of the big size samples the temperature distribution in growth volume corresponds to requirements for growing of structurally perfect single diamond crystals

CORROSION OF IRON-BASE ALLOYS VERSUS ALTERNATE MATERIALS IN GEOTHERMAL BRINES (Interim Report - Period Ending October 1977)

This geothermal corrosion program is to determine why geothermal brines are so corrosive to economical iron-base alloys. The program involves tests of many materials in high pressure equipment where a wide variety of brine chemistries can be studied. The validity of these lab tests is checked by field tests in actual geothermal brine. A series of 30 refreshed autoclave tests and one field test have been completed to define how various chemical components in geothermal brines affect uniform corrosion of 35 materials

An investigation of complex shapes during low pressure tube hydroforming

Hollow structures made of Advanced High Strength Steel (AHSS) are increasingly used in the automobile industry for crash and structural components. Generally high pressure hydroforming is used to form these tabular parts, which is a costly manufacturing process due to the high pressure equipment and large tonnage presses required. A new process termed low pressure hydroforming, where a pressurized tube is crushed between two dies, represents a more cost effective alternative due to the lower pressures and die closing forces required.In this study the low pressure tube hydroforming of one simple and two different complex hollow shapes is investigated. The complexities of the pat1S compared to simple shapes are critically studied and the die filling conditions are investigated and discussed. FUl1hennore the thickness distributions over the circumference of the part during forming are analyzed.<br /

An optimised scalable synthesis of H2O@C60and a new synthesis of H2@C60

New high-yielding synthetic routes to the small-molecule endofullerenes H2O@C60, D2O@C60 and H2@C60 are described. The use of high temperatures and pressures for the endohedral molecule incorporation are avoided. A new partial closure step using PPh3, and final suturing using a novel Diels–Alder/retro-Diels–Alder sequence are amongst the advances reported

Solubility of Nitrogen in Austenitic Iron under High Nitrogen Pressure and Thermodynamic Properties of Iron-Nitrogen Interstitial Solid Solution

Studies on the equilibrium between austenitic iron and nitrogen under various conditions of the maximum pressure of 920 kg/cm^2 and the temperature range from 950°to 1300℃ were carried out by using a high temperature and high pressure equipment. It was shown that the concentration of nitrogen in austenite deviated from Sieverts\u27 law with increasing pressure. The casue for such discrepancy was considered thermodynamically and statistically. That is, the experimental result can reasonably be explained from the geometrical consideration that the chemical potential of a nitrogen atom in austenite, in case of a high nitrogen content deviates remarkably from that in an idial random interstitial solid solution, since each intestitial atom added excludes other interstitial atoms from the seven adjacent sites. Thus, the activity of nitrogen in austenitic iron can be expressed by the following equations : log a_N=log N_N/1-9N_N+ 3.34-427/T for the standard state of nitrogen gas 1 atm pressure, a_N=f^_ log a_N=log N_N/1-9N_N for the standard state of infinitely dilute solid solution

Facile Protocol for Water-Tolerant “Frustrated Lewis Pair”-Catalyzed Hydrogenation

Despite rapid advances in the field of metal-free, “frustrated Lewis pair” (FLP)-catalyzed hydrogenation, the need for strictly anhydrous reaction conditions has hampered wide-scale uptake of this methodology. Herein, we report that, despite the generally perceived moisture sensitivity of FLPs, 1,4-dioxane solutions of B(C6F5)3 actually show appreciable moisture tolerance and can catalyze hydrogenation of a range of weakly basic substrates without the need for rigorously inert conditions. In particular, reactions can be performed directly in commercially available nonanhydrous solvents without subsequent drying or use of internal desiccants

Pressure-Induced Alterations in the Protein Pattern of the Thermophilic Archaebacterium Methanococcus thermolithotrophicus

Elevated hydrostatic pressure has been shown to affect the growth rate of the thermophilic methanobacterium Methanococcus thermolithotrophicus without extending its temperature range of viability. Analysis of the cell inventory after approximately 10 h of incubation at 65 degrees C and 50 MPa (applying high-pressure liquid chromatography and two-dimensional gel electrophoresis) proved that pressure induces alterations in the protein pattern and the amino acid composition of the total cell hydrolysate. Gels showed that after pressurization a series of (basic) proteins with a molecular mass in the range of 38 and 70 kilodaltons occurs which is not detectable in cells grown at normal atmospheric pressure. The question of whether the observed alterations are caused by the perturbation of the balance of protein synthesis and turnover or by the pressure-induced synthesis of compounds analogous to heat shock proteins remains unanswered