Synthetic diamonds are the subject of research in many different implementations. Recognition of the properties of materials with dimensions near the nanometre scale is of great importance for essential science and multiple applications. Microdiamonds synthesised by the HPHT method and nanodiamonds made by detonation were evaluated using XRD, SEM, TEM and Raman spectroscopy. UV-VIS luminescence measurements were performed and compared with each other to assess the surface defects and grain size influence on their optical properties.

A low wear resistance is a significant disadvantage of magnesium-based alloys widely used in industry. The results of plasma electrolytic oxidation (PEO) carried out in an aqueous-alkaline phosphate electrolyte with the addition of hexagonal boron nitride (h-BN) powder to obtain coatings with greater wear resistance on the surface of AZ31 magnesium alloy are presented. The PEO method is one of the most promising for surface treatment of magnesium alloys, since oxidation is carried out in alkaline aluminate, silicate or phosphate electrolytes with various functional additives. The addition of nanocrystalline hexagonal h-BN powder in the form of a suspension into the electrolyte volume does not affect the electrical parameters of PEO, and h-BN particles are incorporated into the structure of the formed composite coating, increasing the wear resistance. It is shown that the resulting coatings have a relief typical of PEO with developed morphology and porosity, which change depending on the oxidation time. In this case, the incorporation of h-BN particles into the coating occurs by an inert mechanism, since they do not undergo chemical transformations with the formation of new phases. Composite coatings obtained on the surface of the AZ31 magnesium alloy by the PEO method consist of crystalline phases of MgO and Mg3(PO4)2, regardless of the addition of h-BN particles to the electrolyte. The wear resistance of coatings is 6 – 8 times higher compared to the untreated alloy. The results obtained can be used to produce PEO coatings with increased wear resistance and use them in various sectors of the economy.

The objective was to study the risk factors, outcomes of infections caused by colistin-resistant K. pneumonia (CRKP) and to evaluate the sensitivity of these microorganisms to antibacterial agents to determine the most adequate antibiotic therapy options.Materials and methods. Klebsiella pneumoniae strains isolated in the ICU of an acute care hospital between October 2020 and August 2022 were included in the study. Microorganisms were identified using an automatic analyzer PHOENIX. The determination of antibiotic sensitivity was studied by the method of serial micro-dilutions in agar with the determination of MIC EUCAST criteria were used to interpret sensitivity. Detection of carbapenemases was carried out by PCR. Clinical efficacy of starter therapy was evaluated as recovery/improvement and no effect.Results. The infection was characterized by a severe course in 58.9 % of patients, with SOFA scores ranging from 1 to 16 points (mean 5.8 points). 88.2 % of patients had received prior antibiotics, most commonly carbapenems. CRKP infections occurred more frequently in older men with comorbidity. The clinical efficacy of initial antibiotic therapy was 41.2 %. In 47.1 % of cases, there was no effect, which required adjustment of therapy. Excluding patients in whom it was impossible to evaluate the effect, eradication was achieved in 33.3 % of patients. 64.6 % of patients were discharged or transferred to another hospital; 6 patients died between 5 and 41 days after diagnosis of CRKP infection. Fatal outcome was more frequent in women ( p=0.042), patients with higher comorbidity index (p=0.027), in case of sepsis and/or septic shock ( p=0.011), and in earlier detection of CRKP after hospitalization ( p<0.001).Conclusion. The efficacy of initial antibiotic therapy after detection of CRKP infection has been shown to be associated with patient survival and reduced risk of mortality with an odds ratio of 3.5. We also identified risk factors for mortality in CRKP infection: comorbidity, sepsis, duration of hospitalization and female gender.

АКТУАЛЬНОСТЬ: Заболеваемость тяжелым острым панкреатитом и летальность пациентов остаются высокими. Важнейшим направлением терапии является купирование эндотоксикоза. Вопрос применения экстракорпоральной детоксикации (ЭКД) остается дискуссионным. ЦЕЛЬ ИССЛЕДОВАНИЯ: Улучшение результатов лечения пациентов с тяжелым острым панкреатитом путем применения методов ЭКД. МАТЕРИАЛЫ И МЕТОДЫ: В исследование включены 25 пациентов. Группа 1 (ЭКД) включала 9 пациентов, применяли стандартную терапию с селективной гемоперфузией (СГ) и продленной вено-венозной гемофильтрацией (ПВВГФ). Группа 2 (контроль): 16 пациентов получали стандартную терапию. Выполняли сравнительный анализ основных клинико-лабораторных показателей и исходов лечения между группами. РЕЗУЛЬТАТЫ: Применение ЭКД позволило снизить количество лейкоцитов с 14,9 до 8,6 × 109/л к 5-м суткам терапии в группе 1 и с 17,6 до 16,1 × 109/л группы 2 соответственно. Динамика концентрации С-реактивного белка с 1-х по 5-е сутки изменилась с 315,6 до 184,6 мг/мл и 274,2 до 352,9 мг/мл в группе 1 и группе 2 соответственно. Уровень концентрации прокальцитонина (PCT) в 1–5-е сутки снизился с 4,5 до 2,1 нг/мл и 3,95 до 6,9 нг/мл в группе 1 и группе 2 соответственно. Концентрация интерлейкина-6 снизилась с 1624,3 до 914,3 пг/мл в группе 1 и повысилась с 1529,8 до 1861,8 пг/мл в группе 2. Динамика рН в группе 1 составила с 7,14 до 7,4 к 5-м суткам терапии и с 7,13 до 7,22 в группе 2. Показатели по шкале SOFA к 5-м суткам в группе 1 составили 4 балла, в группе 2 — 11 баллов. ВЫВОДЫ: Применение СГ и ПВВГФ в комплексной интенсивной терапии сопровождается регрессом маркеров эндогенной интоксикации, разрешением кислотно-основного состояния и уменьшает выраженность органной дисфункции и риска неблагоприятного исхода по сравнению со стандартным лечением.

The addition of Cr nanoparticles to a plasma electrolytic oxidation (PEO) electrolyte offers the possibility of producing layers with a broader range of coating compositions and improved properties. In this study, the effects of nanoparticles and various voltages on coating formation, microscopic morphology, and phase composition were investigated with in situ incorporation of Cr nanoparticles into PEO-coated Mg alloy. The results show that the corrosion performance of the coating was significantly improved when the final voltage was set to 460 V and the concentration of Cr nanoparticles was 1 g/L. Compared to the particle-free coating, the corrosion current density of the coating with the addition of 1 g/L Cr nanoparticles was reduced by two orders of magnitude. The impedance at the low frequency (0.01 Hz) increased by more than one order of magnitude after one hour of immersion, indicating a considerable improvement in corrosion resistance. Due to the high temperature during the coating-formation process, the Cr nanoparticles were oxidized, resulting in the formation of Cr2O3. The existence of Cr2O3 slightly increased the growth rate of the coating and sealed the open pores of the coating.

INTRODUCTION: Creation of protocols for effective empiric antimicrobial therapy is impossible without the analysis of current antibiotic susceptibility data. OBJECTIVE: Analysis of changes in the etiological significance of the leading pathogens of bacteremia in the ICU (intensive care unit) in the period from 2003 to 2021, and their sensitivity to antibiotics; study of the types of carbapenemases in the most relevant pathogens — Klebsiella pneumoniae and Acinetobacter baumannii. MATERIALS AND METHODS: The analysis included all microorganisms isolated from the blood of patients who were in the medical 12-bed ICU in the emergency hospital of Moscow in the period from 2003 to 2021. Identification of microorganisms and determination of antibiotic sensitivity were carried out with an automatic PHOENIX analyzer and a standardized disco diffusion method. Detection of carbapenemases was carried out by PCR (polymerase chain reaction). RESULTS: In the period from 2003 to 2021, 17 034 blood samples were examined, from which 6372 microorganisms were isolated. During this period, the proportion of Gram-negative microorganisms increased from 21.0 to 52.8 %, mainly due to K. pneumoniae from 1.0 to 24.5 % and A. baumannii from 0 to 9.1 %. The resistance of these microorganisms to carbapenems increased significantly from 2008 to 2021: K. pneumoniae from 2.3 % to 70.3 %, A. baumannii — from 7.5 to 99.5 %. K. pneumoniae produced the following types of carbapenemases: OXA-48 (73.8 %), KPC (6.2 %), NDM 1.5 %, NDM + OXA-48 (15.4 %), KPC + OXA-48 (3.1 %). All A. baumannii strains produced OXA-40 type carbapenemase. OXA-48 carbapenemase producers were resistant to colistin and tigecycline in 14.6 and 44.8 %, and to ceftazidime/avibactam in 4.2 %. CONCLUSIONS: The increased level of antimicrobial resistance in recent years among Gram-negative microorganisms isolated from blood is a very significant problem in the ICU. Most K. pneumoniae strains are characterized as multi-drug resistant, about 10 % of the strains were categorized as extremely-drug resistant (XDR) or pan-drug resistant. All strains of A. baumannii belong to the category of XDR.

INTRODUCTION: Septic shock is the most serious complication in intensive care that associates with significant mortality. Extracorporeal hemocorrection may improve treatment of patients with septic shock. OBJECTIVE: Evaluation of the effect of hemocorrection with the multimodal adsorbent device Efferon LPS on the dynamics of organ dysfunction and inflammation markers in patients with septic shock. MATERIALS AND METHODS: A multicenter randomized controlled study was conducted in four clinical organizations in the city of Moscow from March 2021 to May 2022. The study included 58 patients (29 men and 29 women) with septic shock. Randomization was performed in a ratio of 2:1 (hemoperfusion: control). Within 24 hours of enrollment in the study, selective hemoperfusion procedures were performed or standard therapy was used. Hemosorption using Efferon LPS was performed twice, with an interval of 24.5 (23.3–26.0) hours. RESULTS: The use of the multimodal selective hemosorbent Efferon LPS significantly reduced the severity of multiple organ failure (MOF) in patients with septic shock from 7 to 3 points on the SOFA scale after 72 hours by improving hemodynamics, respiratory and renal function. In contrast to the control group, in the Efferon LPS group, the levels of CRP, PCT and IL-6 significantly decreased in 72 hours. The severity of MOF significantly correlated with the level of CRP and PCT (Spearman’s r = 0.346 and r = 0.444, respectively). The duration of hospitalization in survived patients was 16.1 days and 30.1 days in the Efferon LPS and control group, respectively (p = 0.032). The need for a renal replacement therapy (RRT) in survivors by the 3rd day was significantly reduced only in the Efferon LPS group — from 73.7 to 33.3 %. CONCLUSIONS: The use of the selective hemosorbent Efferon LPS resulted in significant decreases the hallmarks of systemic inflammation, MOF and requirements for RRT in patients with septic shock.

Background. The difficulties of antibacterial therapy of infections caused by carbapenemase-producing gram-negative bacteria are associated with limited options for adequate therapy since, in addition to resistance to carbapenems and other beta-lactams, these microorganisms are often characterized by associated resistance to other classes of antibiotics, including polymyxins. In vitro data support the idea of combined use of inhibitor-protected cephalosporins with aztreonam for the treatment of such infections. The aim of the study was to investigate the effectiveness of cefepime/sulbactam (FEP/SB) in combination with aztreonam (ATM) in infections caused by class B and D carbapenemase producers.Methods. A prospective observational study evaluated the effectiveness of the combination of FEP/SB + ATM in ICU patients with nosocomial infections complicated by sepsis or septic shock caused by carbapenem-resistant pathogens with documented production of class B or D carbapenemase. The ineffectiveness of previous treatment and the absence of other options for adequate therapy were used as inclusion criteria. Microbiological, clinical efficacy, and 30-day mortality were indicators of therapy evaluation.Results. The study included 25 patients with nosocomial infection (76% of them was VAP), with sepsis (60%) or septic shock (40%) and an average SOFA score of 6 points caused by Klebsiella pneumoniae (23 patients) or Pseudomonas aeruginosa (2) producing carbapenemases OXA-48 (56%), NDM (20%), NDM + OXA-48 (16%), and class B carbapenemase in two strains of P. aeruginosa. The average daily dose of FEP/SB and ATM was 6.6 g, the duration of therapy was 9.9 days. As a result of the treatment, eradication was achieved in 68% of patients, clinical efficacy was 72%, and the 30-day mortality rate was 28%.Conclusion. Our results show good clinical and bacteriological efficacy of the combination of FEP/SB and ATM in infections caused by extremely resistant K. pneumoniae, non-susceptible to carbapenems and producing class B or D carbapenemase.

АКТУАЛЬНОСТЬ: Септический шок считается наиболее серьезным осложнением в интенсивной медицине и сопровождается значительной летальностью. Экстракорпоральная гемокоррекция может улучшить результаты лечения пациентов с септическим шоком. ЦЕЛЬ ИССЛЕДОВАНИЯ: оценка влияния гемокоррекции с помощью мультимодального адсорбента «Эфферон ЛПС» на динамику органной дисфункции и маркеры воспаления у пациентов с септическим шоком. МАТЕРИАЛЫ И МЕТОДЫ: Мультицентровое рандомизированное контролируемое исследование проведено в четырех медицинских организациях города Москвы (НИИ СП им. Н.Ф. Склифосовского ДЗМ, ГКБ № 1 им. Н.И. Пирогова ДЗМ, ГКБ им. С.С. Юдина ДЗМ, ГКБ № 68 им. В.П. Демихова ДЗМ) с марта 2021 г. по май 2022 г. В исследование включены 58 пациентов (29 мужчин и 29 женщин) с септическим шоком. Рандомизацию проводили в соотношении 2:1 (гемоперфузия: контроль). Не позднее 24 ч после включения пациента в исследование выполняли процедуры селективной гемоперфузии или использовали стандартную терапию. Гемосорбцию с использованием «Эфферон ЛПС» проводили двукратно, с интервалом 24,5 (23,3–26,0) ч. РЕЗУЛЬТАТЫ: Применение селективного гемосорбента «Эфферон ЛПС» позволило уже через 72 ч снизить тяжесть органной дисфункции у пациентов с септическим шоком с 7 до 3 баллов по шкале SOFA (Sequential Organ Failure Assessment) за счет улучшения гемодинамики, респираторной и почечной функции. В отличие от контрольной группы, в группе «Эфферон ЛПС» уже через 72 ч значимо снижался уровень С-реактивного белка (СРБ) в 1,5 раза, прокальцитонина (ПКТ) — в 2,7 раза, интерлейкина-6 — в 2,3 раза. Тяжесть органной дисфункции значимо коррелировала с уровнем СРБ (r = 0,346) и ПКТ (r = 0,444). Длительность госпитализации выживших пациентов составила 16,1 и 30,1 дня в группе «Эфферон ЛПС» и контрольной группе соответственно (p = 0,032). Потребность в проведении заместительной почечной терапии у выживших к 3-м суткам значимо снижалась с 73,7 до 33,3 % только в группе «Эфферон ЛПС», но не в контрольной группе. ВЫВОДЫ: Применение селективного гемосорбента «Эфферон ЛПС» позволило уменьшить выраженность системного воспаления и значимо снизить тяжесть органной дисфункции у пациентов с септическим шоком за счет улучшения показателей гемодинамики, газообмена и почечной функции.

Laser-induced white emission of diamond was investigated under irradiation with a focused beam of an infrared laser diode. It is a surface-related coherent emission, characterized by an excitation threshold and an exponential dependence on pumping laser power. The mechanism of white emission is discussed in terms of multiphoton ionization of carbon atoms in an irradiated spot. The excitation power dependence of white emission intensity has demonstrated hysteresis loop behavior. This phenomenon could be useful in new broadband laser sources and optical information storage.

ЦЕЛЬЮ Обзора является анализ данных литературы о перспективах и безопасности продленной седации ингаляционными анестетиками с применением устройства для ингаляционной седации испарителя AnaConDa в отделениях интенсивной терапии и реанимации. Анализ результатов исследований показал, что применение продленной ингаляционной седации в отделении реанимации пациентам, находящимся в критическом состоянии, способствует ранней активизации и реабилитации благодаря хорошей управляемости, сокращает время пребывания на искусственной вентиляции легких, оказывает нейропротекторное, кардиопротекторное, противовоспалительное, антиконвульсантное, бронходилатирующее действие, обеспечивая ряд положительных эффектов при относительно простой и безопасной технике выполнения. Можно заключить, что исследователям еще только предстоит установить преимущества или недостатки седации ингаляционными анестетиками по сравнению с седацией внутривенными препаратами в повседневной клинической практике.

INTRODUCTION: Morbidity and mortality of severe acute pancreatitis (SAP) remains high. The most important direction of therapy is the relief of endotoxicosis. The use of extracorporeal detoxification (ECD) is a debatable problem. OBJECTIVE: Improving the results of treatment of patients with SAP, through the use of ECD methods. MATERIALS AND METHODS: The study included 25 patients. Group 1: ECD included 9 patients who used standard therapy with selective hemoperfusion (HP) and continuous veno-venous hemofiltration (CVVHF). Group 2 (control) 16 patients received standard therapy. We performed a comparative analysis of the main clinical and laboratory parameters and treatment outcomes between the groups. RESULTS: The use of ECD allowed to reduce the number of leukocytes from 14.9 to 8.6 × 109/l by 5 days of therapy in group 1, and from 17.6 to 16.1 × 109/l in group 2, respectively. The dynamics of CRP concentration from 1 to 5 days changed from 315.6 to 184.6 mg/ml and 274.2 to 352.9 mg/ml in groups 1 and 2, respectively. The level of PCT concentration on days 1–5 decreased from 4.5 to 2.1 ng/ml and 3.95 to 6.9 ng/ml in groups 1 and 2, respectively. The concentration of IL-6 decreased from 1624.3 to 914.3 pg/ml in group 1, and increased from 1529.8 to 1861.8 pg/ml in group 2, respectively. The dynamics of pH in group 1 was from 7.14 to 7.4 by the 5th day of therapy and 7.13 to 7.22 in group 2, respectively. SOFA by day 5 in group 1 was 4 points and 11 points in group 2, respectively. CONCLUSIONS: The use of HP and CVVHF in complex intensive care is accompanied by a significant regression of markers of endogenous intoxication, resolution of the acid-base state and reduces the severity of organ dysfunction and the risk of adverse outcomes, compared with standard treatment.

Rhabdomyolysis (RM) is a clinical and laboratory syndrome with the underlying destruction of myocytes and the release of intracellular debris into the systemic circulation. In more than 55% of cases, RM is complicated by acute kidney injury (AKI), which necessitates various methods of extracorporeal detoxification and currently is a controversial issue. Aim : to improve the results of treatment of patients with RM of toxic origin complicated by AKI by using early selective hemoadsorption (SH). Material and methods . The study included 36 patients divided into 2 groups. Group 1 included 24 patients who received standard therapy and hemodiafiltration (HDF) as a life-saving intervention. Group 2 comprised 12 patients who underwent early SH to prevent the progression of AKI. We performed a comparative analysis of clinical and laboratory parameters and treatment outcomes in the groups. Results. The use of SH was associated with reduced level of myoglobin on day5 of therapy from 384.1 to 112.4 gg/l (70.7%) vs 335.15 to 219.1 gg/l (34.6%) reduction in the conservative therapy group. By day 7, this parameter was 18.8 (95.1%) and 142.4 (57.5%), respectively (7=0.012). The level of cystatin-C decreased on day 5 from 17.3 to 3.2 mg/l (81.5%) in group 2 and from 14.9 to 11.7 mg/l (21.5%) in group 1. By day 7, this parameter decreased to 2.5 (85.6%) and 14.1 (5.3%) mg/l, respectively (7=0.001). The length of ICU stay in group 2 was 7 (6; 9) days, while in the conservative therapy group it was 12 (7; 13) days (7=0.04). The hospital stay was 12 (10; 16) and 22 (14,5; 24,5) days, respectively (7=0.028). Conclusion . The early use of SH in the intensive therapy helped decrease the levels of markers of endogenous intoxication, AKI severity, improve the filtration capacity of the kidneys, and reduced the length of stay in the ICU and hospital.

Synthetic diamonds are the subject of research in many different implementations. Recognition of the properties of materials with dimensions near the nanometre scale is of great importance for essential science and multiple applications. Microdiamonds synthesised by the HPHT method and nanodiamonds made by detonation were evaluated using XRD, SEM, TEM and Raman spectroscopy. UV-VIS luminescence measurements were performed and compared with each other to assess the surface defects and grain size influence on their optical properties.

Sr2FeMoO6–δ single-phase samples without Fe/Mo cations superstructural ordering (P) and with Curie temperature 407 K were obtained by the solid-phase technique. According to the XRD data, the growth dynamics of the parameter P is nonlinear. In this case, the process of reaching maximum values of P (Pmax) is long and its rate is several times lower than the change of the oxygen index 6–δ. It was found that with increasing temperature of isothermal annealing, P increases and reaches maximal values 88 % at T = 1320 K for 120 h, Pmax = 92 % at T = 1420 K for 100 h, while Pmax = 90 % at T = 1470 K for 45 h. One can assume that the lower values of Pmax at T = 1470 K than at T = 1420 K are due to the influence of thermal energy on the destruction of chain ordering of Fe and Mo cations placed in staggered order. Based on the analysis of P time dependences, two relaxation processes can be found and the dP/dt = ¦(t) can be divided into two regions – I and II. In the region I the relaxation time is shorter than that in the region II. The point is that the ordering of cations in the –O–Fe–O–Mo–O chains in the region I requires atomic displacements by approximately one interatomic distance, whereas in the region II cation displacements occur over long distances with the formation of long[1]chain long-range ordering.

In this work, solid solutions of La0.7Sr0.3Mn0.95Fe0.05O3-δ with different oxygen content were obtained by the solid-phase reactions technique. Based on the investigation of the dynamics of changes in the oxygen index (3 – δ) during heating of the samples, the formation of a stressed state in their grains as a result of annealing was established. This results in a decrease in the mobility of oxygen vacancies during the reduction of cations according to the Mn4+ + e– → Mn3+ scheme and explains the decrease of released oxygen amount with an increase of δ as well as the heating rate of the samples. When studying the magnetic properties of the obtained samples, it was found that the temperature dependence of the magnetization obeys the Curie–Weiss law and as the oxygen defficiency increases, the Curie temperature for solid solutions decreases. It was found that the particles are in a frozen ferromagnetic state when measured in the low-temperature region of the М (Т) dependence in “zero-field mode” at Т ˂ ТВ. The presence of ferromagnetism at Т ˃ ТВ leads to a magnetically ordered state, in which the resulting magnetic moment of the magnetic particle is influenced by thermal fluctuations. When considering the temperature values of the magnetization of lanthanum-strontium manganite samples, it was found that with an increase of temperature in the low-temperature region, magnetic ordering is disturbed due to the excitation of magnons with a quadratic dependence of the energy from the wave vector, the number of which increases in proportion to T3/2. This results in a decrease in the manganite magnetization. The observed temperature dependence of the magnetization measured in the “field-cooling mode” was approximated taking into account the quadratic and non-quadratic dispersion laws of the magnon spectrum.

Synthetic diamonds are the subject of research in many different implementations. Recognition of the properties of materials with dimensions near the nanometre scale is of great importance for essential science and multiple applications. Microdiamonds synthesised by the HPHT method and nanodiamonds made by detonation were evaluated using XRD, SEM, TEM and Raman spectroscopy. UV-VIS luminescence measurements were performed and compared with each other to assess the surface defects and grain size influence on their optical properties.

It has been established that in lithium fluoride crystals, subjected to pre-irradiation thermal shocks or compression, intrinsic point defects with new properties different from the known properties of the usual defects of the same composition are formed as a result of irradiation. The obtained new properties are similar to those for radiation-induced defects that were previously registered in nanocrystals and called near-cluster defects. It is shown that the combination of pre-irradiation heating and compression of a crystal increases the ratio of the concentrations of formed near-cluster and usual defects.

The paper provides the information on the effects of rapid (1 min) high pressure high temperature (RHPHT) annealing of synthetic Ib-type diamond plates at temperatures (1900 degrees C, 2100 degrees C, 2300 degrees C, 2500 degrees C, 2700 degrees C) and pressure of 8 GPa. The studies were carried out using the visual analysis, absorption and Raman spectroscopy, photoluminescence and cathodoluminescence. During RHPHT annealing the diamond plates in a high-pressure container were rapidly heated/cooled at a very non-uniform temperature and pressure distribution. All this caused the inhomogeneous plastic deformation of diamond plates. The plastic deformation of diamonds during RHPHT annealing was a powerful "generator" of vacancies. The electron transfer from individual atoms of substituting nitrogen to nitrogen-vacancy centers switched these centers to a negatively charged state. Another accompanying RHPHT annealing process was the diffusion of nitrogen atoms with the formation of it's simple aggregates - H3 defects (at 2300 degrees C). At higher RHPHT annealing temperatures more complex aggregates containing three nitrogen atoms - N3 defects - were generated. RHPHT annealing led to the formation of identical nitrogen e vacancy defects, as did quasi stationary HPHT annealing, but the number of these defects was significantly greater after RHPHT annealing. (C) 2020 Elsevier Ltd. All rights reserved.

The paper presents the investigations of laser-induced white light emission (LIWE) and structural changes in diamonds after continuous wavelength near infrared laser excitation. Micro-size diamonds were synthesized using high pressure high temperature method and then excited using continuous wavelengths near infrared (808, 975, 1064 nm) laser diodes in vacuum. The structure and morphology of the samples were investigated before and after laser excitation using XRD, Raman spectroscopy and SEM/FIB and TEM microscopy. Broadband, intense, anti-Stokes LIWE with very low threshold were observed. LIWE resulted in the graphitization of the diamond grain surface with different stages of graphitization depending on the excitation time. A model of an sp(2)-sp(3) hybridization switch process assisting the multiphoton ionization and free to bound recombination of electron between two carbon atoms were proposed. (c) 2019 Elsevier Ltd. All rights reserved.