Visualization the electrostatic potential energy map of graphene quantum dots

Graphene quantum dots (GQDs) represent single layers up to dozens of graphene layers smaller than 30 nm. GQDs are newish molecules that have aroused great interest in research because of their exceptional and manageable optical, electrical, chemical, and structural properties. In this work, we report electrostatic potential energy maps, or molecular electrostatic potential surfaces, illustrate the charge distributions of GQDs three-dimensionally. Knowledge of the charge distributions can be used to determine how GQDs interact with one another. To analyze the distribution of molecular charges accurately, a large number of electrostatic potential energy values must be calculated. The best way to transmit these data is to visualize them as in the electrostatic potential map. A ZINDO semi-empirical quantum chemistry method then imposes the calculated data onto an electron density model of the GQDs derived from the Schr\"odinger equation. To make the electrostatic potential energy data of GQDs easy to interpret, a color spectrum, with red as the lowest electrostatic potential energy value and blue as the highest, is employed to convey the varying intensities of the electrostatic potential energy values. The results of the four GQD models suggest that the energy of the ionization potential lies in a range of -7.20 eV to -5.31 eV and the electron affinity is -2.65 to -0.24 eV.Comment: 2nd International Conference and Exhibition on Powder Technology (ICePTi) 201

Analysis Cracking Corrosion on Carbon Steel Pipes API 5L-X65 In Solution 7700 ml Aquades, 250 ml Acetic Acid and 50 ml Ammonia with Gas CO2 and H2S in Saturation Condition

The oil and gas industry exploration that will generally be followed by corrosive substances including sweet gas (eg H2S and CO2), it will result in corrosion event. The corrosion stress cracking will cause the carbon steel pipe to break so that production oil and gas can be stopped. The research aims in this paper is to analyze the corrosion event of carbon steel pipe in laboratory scale on acid environment with the existence of sweet gas H2O and CO2 by using three points loading method. This research uses carbon steel pipe API 5L-X65 which stay in condensation environment of 7700 ml aquades, 250 ml acetic acid and 50 ml ammonia, then filled sweet gas CO2 and H2S in saturated state. Based on the test results of microstructure and microscope polarized, there is a phenomenon corrosion stress cracking, i.e transgranular stress cracking corrosion and intergranular stress cracking corrosion. The accelerate corrosion that happened at the test sample will be greater if ever greater given deflection for the time of the same presentation. Crack deepness in the test of the test sample will deeper if ever greater given deflection. The cracks in the sample test will deeper if it was given stress σ greater for the same exposure time

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

El Eco de Santiago : diario independiente: Año VI Número 1850 - 1901 Febrero 26

Pada eksplorasi di industri migas bahwa umumnya akan diikuti dengan zat korosif termasuk sweet gas (misalnya H2S dan CO2), maka akan mengakibatkan terjadinya peristiwa korosi. Bila terjadi peristiwa korosi retak tegangan akan mengakibatkan pipa baja karbon pecah sehingga berdampak produksi migas bisa terhenti. Penelitian ini bertujuan untuk menganalisis peristiwa korosi pipa baja karbon skala laboratorium dalam lingkungan asam dengan adanya sweet gas H2O dan CO2 dengan menggunakan metoda tiga titik pembebanan. Penelitian ini menggunakan bahan pipa baja karbon API 5L-X65 yang berada dalam lingkungan larutan asam asetat dan amoniak, kemudian diisikan sweet gas CO2 dan H2S dalam keadaan jenuh. Berdasarkan hasil uji mikrostruktur dan mikroskop terpolarisasi, terjadi peristiwa korosi retak tegangan, yaitu korosi retak tegangan transgranular dan korosi retak tegangan intergranular. Laju korosi yang terjadi pada sampel uji akan semakin besar, apabila defleksi yang diberikan semakin besar. Dalamnya retakan pada sampel uji akan semakin dalam apabila defleksi yang diberikan semakin besar. Laju korosi pada sampel uji akan semakin besar untuk defleksi yang sama tetapi variasi waktu paparan berbeda

ANALISA FENOMENA KOROSI PADA PIPA BAJA KARBON API 5L-X65 DENGAN METODA PEMBEBANAN TIGA TITIK PADA LINGKUNGAN GAS H2S DALAM KONDISI JENUH CO2 DALAM LARUTAN 7900 ML AIR LAUT DAN 100 ML AMONIAK

Results of the research shows that material test sample using plate carbon steel pipe API 5L-X65 is in chamber.The corrosion phenomenon occurs in research using the three point loading method in the CO2 environmentand saturated H2S gas in a solution of 7900 ml of sea water and 100 ml ammonia. The corrosion occurs are thetransgranular and intergranular stress corrosion cracking based on the result of microstructure test andpolarized microscopy test. The corrosion rate will increase as the deflection given to the test sample is becomelarger for the same exposure time, and the inside crack will deepen as the deflection given to the sample test isbecome larger forthe same exposure time. The corrosion rate with deflection variation based on the results ofthe graph is y=0.2511x2- 0.0209x - 0.0209 for 336 hours exposure time, y = 0.3871x2 - 0.3819x + 0.3296 for672 hours exposure time, y = 0,1046x2 - 0,1221x + 0,1674 for 1008 hours exposure time and y = 0.0942x2 +0.0837x - 0.0288 for 1344 hours exposure time.Hasil penelitian menunjukkan bahwa bahan sampel uji menggunakan pelat pipa baja karbon API 5L-X65berada dalam chamber. Dengan penelitian menggunakan metoda tiga titik pembebanan yang beradadilingkungan gas CO2 dan gas H2S jenuh dalam larutan 7900 ml air laut dan 100 ml amoniak maka terjadilahperistiwa fenomena korosi. Peristiwa korosi yang terjadi adalah korosi retak tegangan transgranular danintergranular berdasarkan dari hasil uji mikrostruktur dan berdasarkan dari hasil uji mikroskop terpolarisasi.Laju korosi yang terjadi akan semakin meningkat seiring dengan defleksi yang diberikan pada sampel uji yangsemakin besar untuk waktu paparan yang sama, dan kedalamancrack akan semakin bertambah seiring dengandefleksi yang diberikan pada sampel uji yang semakin besar untuk waktu paparan yang sama. Laju korosidengan variasi defleksi berdasarkan hasil dari grafikadalah y = 0,2511x2 - 0,0209x – 0,0209 untuk waktupaparan 336 jam, y = 0,3871x2 – 0,3819x + 0,3296 untuk waktu paparan 672 jam, y = 0,1046x2 – 0,1221x +0,1674 untuk waktu paparan 1008 jam dan y = 0,0942x2 + 0,0837x - 0,0288 untuk waktu paparan 1344 jam

Carbon quantum dots with honeycomb structure: a novel synthesis approach utilizing cigarette smoke precursors

Abstract This study presents a novel approach to synthesizing honeycomb carbon quantum dots (CQDs) from cigarette smoke by a hydrothermal process. A comprehensive characterization of these CQDs, conducted through high-resolution transmission electron microscopy (HRTEM), showcases their unique honeycomb structure, with an average particle size of 6.3 nm. Photoluminescence (PL) in CQDs is a captivating phenomenon where these nanoscale carbon structures emit strong blue luminescence at 461 nm upon exposure to ultraviolet light, with their excitation peak occurring at 380 nm. Fourier Transform Infrared (FTIR) analysis also identifies specific functional groups within the CQDs, offering valuable insights into the mechanisms governing their photoluminescence. Analysis of excitation spectra indicates the presence of both aromatic C=C bonds at 254 nm and C–O bonds from 280 to 420 nm

Lipid and metabolite deregulation in BRCA1 and BRCA2 genetic mutations response

Thank you for the opportunity to address quality control issues that took place as part of the initial technology development before commencement of the pilot study. This study comparing women with BRCA1 or BRCA2 and healthy control subjects is continuing as a longitudinal multisite program in Australia, with those women showing deregulation in their breast tissues being evaluated every 6 months

Lipid and metabolite deregulation in the breast tissue of women carrying BRCA1 and BRCA2 genetic mutations

Purpose: To use localized correlated spectroscopy (COSY) to assess for an altered biochemical state or states in breast tissue of women with BRCA gene mutations that potentially constitute preinvasive conditions. Materials and Methods: Institutional review board approval was obtained. Participants provided written informed consent. In vivo localized COSY images were recorded at 3 T in the breast tissue of women carrying BRCA1 (n = 9) or BRCA2 (n = 14) gene mutations and were compared with images in healthy control subjects with no family history of breast cancer (n = 10). All participants underwent contrast material-enhanced MR imaging and ultrasonography (US). Statistical significance was calculated with the Mann-Whitney two-sided nonparametric test. Results: No abnormality was recorded with MR imaging or US. Metabolite levels in the BRCA1 cohort were reduced by 79% (P = .014) when compared with triglycerides level, and there was a 19% increase in lipid unsaturation and triglyceride levels (P = .027 and P = .086, respectively) when compared with cellular cholesterol level. Cholesterol level was reduced by 47% (P = .027) when compared with diallylic lipid level. Metabolite levels in the BRCA2 cohort showed increased unsaturation of 21% (P = .030) relative to triglycerides level. Comparison of the BRCA1 and BRCA2 cohorts showed a 47% (P = .002) increase in cholesterol level in the BRCA2 cohort when compared with diallylic lipid level and a 52% (P = .003) increase when compared with triglycerides level. Levels of diallylic lipid, unsaturated lipid, triglycerides, and terminal methyl on the acyl chain are reduced by 46% (P = .002), 57% (P = .003), 66% (P = .003), and 29% (P = .010), respectively, when compared with cholesterol level. Conclusion: Localized COSY recorded significant changes in women with BRCA1 and BRCA2 gene mutations when compared with control subjects. If these changes are ultimately proven to be a premalignant stage, this method may prove useful in screening

Lipid deregulation in women carrying the BRCA mutations: Non invasive evaluation by two-dimensional spectroscopy

BRCA1 and BRCA2 genes belong to the tumor suppressor family and patients with these genes are at increased risk of developing breast cancer. A BRCA1 or BRCA2 mutation carrier has approximately a 3% risk of getting breast cancer before the age of 30. However, this risk increases to almost 50% when the patient reaches the age of 50 and becomes 50%-80% at the age of 70. BRCA2 mutation carriers have been shown to survive longer than those carrying BRCA1 mutations. This difference has been attributed to increased ovarian deaths in BRCA1 mutation carriers. In this study, we apply in vivo two-dimensional 2D localized correlation spectroscopy (L-COSY) to look for a premalignant state in the breast tissues of apparently healthy women carrying the BRCA gene mutations and others with a family history. We propose the hypothesis that those with the BRCA gene mutations would have altered chemistry reflective of a preinvasive state