Flotation activity of amino alcohols and their derivatives

Results are presented from experimental studies conducted to find derivatives of amino alcohols that can efficiently replace oxal T-80 in the flotation of complex ores: derivatives of 1-, 2-aminoethanol, 1-, 2-, and 1-, 3-aminopropanes, and 3-, 4-substituted amino alcohols of the pyridine and piperidine series. Irkutsk State Technical University, Irkutsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 110–114, July–August, 1999.     

Diverse world of unconventional hydrogen bonds

This Account presents our view of unconventional intermolecular hydrogen bonds (HBs) for organometallic complexes and transition-metal or main-group hydrides. Over the past decade, low-temperature spectroscopic (IR, UV, and NMR) studies combined with theoretical calculations have disclosed the static and dynamic features of different HBs. Their guiding role in the proton-transfer processes was determined, as well as the energetic characteristics of HB intermediates and the activation barriers. Nevertheless, there is still much to explore in terms of the prediction of HB properties and control of protonation/deprotonation processes.     

Study of plastic compounds containing polypropylene and wood derived fillers from waste of different origin

The scope of the article was to study the perspectives of the using of wood derived fillers (WDF) from waste of different origin as fillers of polypropylene. The WDF used in this study was hard wood flour (HW), birch veneer polishing dust (VD) and tetra‐pack carton cellulose fiber (TC). Some mechanical strength parameters, water uptake in the static and cyclic test and resistance to fungal decay of polypropylene (PP) composites containing these three types of WDF were studied and compared with similar loading (40 wt %) talc‐filled PP. Composites containing TC and VD fibers as filler showed the highest flexural strength at three test temperatures (?40, +20, and +40°C) and flexural modulus and tensile strength at plus temperatures. On the other hand talc‐filled PP exhibited greatest flexural modulus at minus temperature, greatest impact strength at room temperature and best flow ability. Significant difference was observed between PP composites with HW and VD fillers regarding water uptake in cyclic tests, however flexural strength and modulus change of composites were reversible after drying. No weight loss of WDF/PP composites was observed after 6 week exposure to brown‐ and white‐rot fungi, however, degradation of the surface of samples was detected by SEM. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Sugar and nutritional extremism

For many, sugar represents a threat to their health, a perception that is driven by increase in the prevalence of obesity, diabetes, and metabolic disorders, which directly or indirectly is connected with the consumption of sugar. However, is sugar to blame for this health crisis, or are sedentary lifestyle and unhealthy diet equally important? Today, sugars and fats are being targeted for restriction or even prohibition. Should we get rid of sugar altogether and/or does it merit a reprieve? Is the effort to “outlaw” sugars a symptom of nutritional extremism that can be as harmful as any other type of extremism?     

Certain methods for eliminating errors due to nonlinear scanning in photo-pulsating instruments

Conclusions The discussed methods for controlling the scaling-pulse frequency as a function of the scanning diaphragm rotation angle serve to eliminate one of the basic errors of photo-pulsating gauges, which is due to the nonlinearity of scanning, and to develop several designs of gauges of the above class for work under different technological conditions.