Технологічні рішення і технічні засоби підвищення екологічної безпеки проведення бурових робіт

Рассмотрено влияние проведения буровых работ на окружающую среду. Приведены рекомендации для повышения экологической безопасности проведения буровых работ. Описаны технологические решения и технические средства уменьшения неблагоприятного влияния бурения нефтегазовых скважин на окружающую среду. В комплексе решены и эффективно внедрены на практике вопросы экологической безопасности проведения буровых работ, утилизации, размещения и захоронения отходов бурения. Дказано, что безамбарное бурение на месторождениях возможно при наличии шламонакопителя и нагнетательной скважины.The environmental impacts of drilling works are considered. A range of recommendations for environmental safety enhancement of drilling works is given. Technological solutions and technical means to reduce adverse environmental impacts of oil and gas wells drilling are described. The issues of drilling works environmental safety, utilization, disposal and burial of waste are jointly solved and successfully implemented. The pit less drilling is proved to be possible for any field under the condition of slurry pond and injection well use

Crystallographic Characterization and Control of Domain Structure within Individual Graphene Islands

Chemical vapor deposition of graphene on Cu foil was performed to clarify the origin of the characteristic domain structure within individual graphene islands grown on variously oriented Cu grain surfaces. While the domain structure strongly affected island shapes on Cu(111) and (101), islands grown on Cu(001) showed that they always had a four-lobed shape regardless of whether they consisted of a single domain or multiple domains. The formation of the specific shape is related to the fact that there are edges in two fast growth directions that were found to have equivalent atomic configurations for the oriented domain. Furthermore, hydrogen etching was found to preferentially act to misoriented domains within the island on Cu(001), leading to single-crystalline four-lobed island formation. Finally, we found an interesting feature in that the ratio of single-crystalline islands increased on the vicinal Cu(001) surface compared with that on the Cu(001) basal plane. Cu(111) microfacets existing on the vicinal surface may play a significant role in the nucleation stage. These findings shed new light on the graphene growth mechanism on Cu surface and may lead the way to enlarging the domain size in the complete graphene layer by means of precise control of the “intra-island” domain structures

Selective Graphene Formation on Copper Twin Crystals

Selective graphene growth on copper twin crystals by chemical vapor deposition has been achieved. Graphene ribbons can be formed only on narrow twin crystal regions with a (001) or high-index surface sandwiched between Cu crystals having (111) surfaces by tuning the growth conditions, especially by controlling the partial pressure of CH₄ in Ar/H₂ carrier gas. At a relatively low CH₄ pressure, graphene nucleation at steps on Cu (111) surfaces is suppressed, and graphene is preferentially nucleated and formed on twin crystal regions. Graphene ribbons as narrow as ∼100 nm have been obtained in experiments. The preferential graphene nucleation and formation seem to be caused primarily by a difference in surface-dependent adsorption energies of reactants, which has been estimated by first principles calculations. Concentrations of reactants on a Cu surface have also been analyzed by solving a diffusion equation that qualitatively explains our experimental observations of the preferential graphene nucleation. Our findings may lead to self-organizing formation of graphene nanoribbons without reliance on top-down approaches in the future

Weights of the body, epidermal fat pads, and liver, and serum levels of biochemical parameters under high-fat dietary conditions.

<p>Wild-type (WT) and IVA-PLA₂-knockout (KO) mice fed normal (N) or high-fat (HF) diets for 8 or 16 weeks were fasted and subjected to each measurement (n = 4–6). FFA, free fatty acid; PL, phospholipids; LPC, lysophosphatidylcholine; ALT, alanine aminotransferase; AST, aspartate aminotransferase.</p>a<p><i>P</i><0.05 versus wild-type mice fed normal diets.</p>b<p><i>P</i><0.05 versus wild-type mice fed HF diets.</p>c<p><i>P</i><0.005 versus wild-type mice fed normal diets.</p

Serum levels of adipokines in wild-type and IVA-PLA₂-knockout mice.

<p>Wild-type and IVA-PLA₂-knockout (KO) mice were fed normal (N) or high-fat (HF) diets for 8 weeks and fasted. The serum levels of adiponectin (A), leptin (B), and resistin (C) were measured (n = 4–6). *<i>P</i><0.05 versus wild-type mice fed normal diets, **<i>P</i><0.05 versus IVA-PLA₂-knockout mice fed normal diets. No significant differences in the serum levels of adipokines were detected between the two genotypes.</p

Microscopic views of epididymal fat pads in wild-type and IVA-PLA₂-knockout mice.

<p>Wild-type and IVA-PLA₂-knockout (KO) mice were fed normal or high-fat (HF) diets for 8 weeks and fasted. Representative epididymal fat pad sections stained with hematoxylin-eosin are shown. Original magnification, ×4. IVA-PLA₂ deficiency suppressed the expansion of epididymal adipocytes induced by HF feeding.</p

Lipoprotein profiles under HF dietary conditions.

<p>Wild-type (WT) and IVA-PLA₂-knockout (KO) mice were fed normal or HF diets for 16 weeks and fasted. The serum levels of VLDL, LDL, and HDL were analyzed. Each trace represents the mean (n = 4–6). IVA-PLA₂ deficiency reduced the increased serum level of LDL by HF feeding.</p

Conduction Tuning of Graphene Based on Defect-Induced Localization

The conduction properties of graphene were tuned by tailoring the lattice by using an accelerated helium ion beam to embed low-density defects in the lattice. The density of the embedded defects was estimated to be 2–3 orders of magnitude lower than that of carbon atoms, and they functionalized a graphene sheet in a more stable manner than chemical surface modifications can do. Current modulation through back gate biasing was demonstrated at room temperature with a current on–off ratio of 2 orders of magnitude, and the activation energy of the thermally activated transport regime was evaluated. The exponential dependence of the current on the length of the functionalized region in graphene suggested that conduction tuning is possible through strong localization of carriers at sites induced by a sparsely distributed random potential modulation