scholarly journals Complexation of copper ions in atmospheric precipitation in Croatia

2008 ◽  
Vol 87 (1) ◽  
pp. 80-87 ◽  
Author(s):  
Marta Plavšić ◽  
Palma Orlović-Leko ◽  
Zlatica Kozarac ◽  
Elvira Bura-Nakić ◽  
Slađana Strmečki ◽  
...  
1965 ◽  
Vol 13 (02) ◽  
pp. 477-483
Author(s):  
Alwin B. Bogert

SummaryExperiments were conducted to determine why different lots of Borate Buffer reagent affect the clot lysis times obtained in the fibrinolytic assay of Streptokinase. Minerals naturally occurring in distilled water were screened individually to determine their influence on lysis. Copper was found to have a very pronounced effect in this regard on the fibrinolytic system in that low levels reduce the lysis time and high levels increase it.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 37-46 ◽  
Author(s):  
PEDRO E.G. LOUREIRO ◽  
SANDRINE DUARTE ◽  
DMITRY V. EVTUGUIN ◽  
M. GRAÇA V.S. CARVALHO

This study puts particular emphasis on the role of copper ions in the performance of hydrogen peroxide bleaching (P-stage). Owing to their variable levels across the bleaching line due to washing filtrates, bleaching reagents, and equipment corrosion, these ions can play a major role in hydrogen peroxide decomposition and be detrimental to polysaccharide integrity. In this study, a Cu-contaminated D0(EOP)D1 prebleached pulp was subjected to an acidic washing (A-stage) or chelation (Q-stage) before the alkaline P-stage. The objective was to understand the isolated and combined role of copper ions in peroxide bleaching performance. By applying an experimental design, it was possible to identify the main effects of the pretreatment variables on the extent of metals removal and performance of the P-stage. The acid treatment was unsuccessful in terms of complete copper removal, magnesium preservation, and control of hydrogen peroxide consumption in the following P-stage. Increasing reaction temperature and time of the acidic A-stage improved the brightness stability of the D0(EOP)D1AP bleached pulp. The optimum conditions for chelation pretreatment to maximize the brightness gains obtained in the subsequent P-stage with the lowest peroxide consumption were 0.4% diethylenetriaminepentaacetic acid (DTPA), 80ºC, and 4.5 pH.


2003 ◽  
Vol 766 ◽  
Author(s):  
Ahila Krishnamoorthy ◽  
N.Y. Huang ◽  
Shu-Yunn Chong

AbstractBlack DiamondTM. (BD) is one of the primary candidates for use in copper-low k integration. Although BD is SiO2 based, it is vastly different from oxide in terms of dielectric strength and reliability. One of the main reliability concerns is the drift of copper ions under electric field to the surrounding dielectric layer and this is evaluated by voltage ramp (V-ramp) and time dependent dielectric breakdown (TDDB). Metal 1 and Metal 2 intralevel comb structures with different metal widths and spaces were chosen for dielectric breakdown studies. Breakdown field of individual test structures were obtained from V-ramp tests in the temperature range of 30 to 150°C. TDDB was performed in the field range 0.5 – 2 MV/cm. From the leakage between combs at the same level (either metal 1 or metal 2) Cu drift through SiC/BD or SiN/BD interface was characterized. It was found that Cu/barrier and barrier/low k interfaces functioned as easy paths for copper drift thereby shorting the lines. Cu/SiC was found to provide a better interface than Cu/SiN.


Author(s):  
А. Kh. Chochaev

The article analyzes problems of the Russia forest complex development related to social, environmental and infrastructure issues, the solution of which is impossible without state participation. The reasons of the poor adaptation of the forest complex market economy to long development periods, as well as the environmental consequences of economic activity, including environmental pollution, depletion of natural resources, loss of biodiversity and damage to public health, are considered. The analysis of the forest complex market economy features is made on domestic and foreign examples, a serious shortcoming of which is the isolation of the investment payback process from the chosen economic development direction. Forest rejuvenation in this way leads to a decrease or even loss of the forests biospheric properties to regulate the surface runoff of atmospheric precipitation and the formation of groundwater reserves. It is known, that in the forests of the European part of Russia have been accumulated large reserves of semi-subsistence conifer and hard wood. It is shown that to involve it in use it is necessary to change the principles of annual use calculations and to actually re-develop the regulatory framework for the intermediate use of forest wood resources. Four forest management units in the forest economy of the forest complex were identified: state forest management and implementation of medium-term and long-term planning of all types of work in forests, taking into account materials of the state forest inventory and assessing the state and trends in the development of domestic and foreign timber markets; protection and protection of forests from fires and other adverse natural factors (insects, fungi, pollution); carrying out planned logging with the differentiated use of all types of wood and the organization of reforestation taking into account the diversity of growing conditions and the possibilities of using the lands of the state forest fund of Russia. It is advisable to create economic mechanisms to stimulate the activities of all enterprises and institutions of the Russia forest complex for the transition to new environmentally sound technologies in the forest. A flexible economic mechanism is needed to include forest management costs in the cost of harvested wood in order to restore the ecological, economic, social and cultural properties of forests.


2020 ◽  
Vol 21 (2) ◽  
pp. 73-76
Author(s):  
V.S. SHIMANOVA ◽  
◽  
L.V. LEONOVA ◽  
I.A. BULATOV ◽  
I.V. ANANINA ◽  
...  

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