Development of the RF Ion Sources for Focused Ion Beam Accelerators

The paper presents the results of investigations of ion sources developed in the IAP of NAS of Ukraine for generation of high brightness ion beams with small energy spread. A series of RF ion sources operated at the frequency of 27.12 MHz were studied: the inductive RF ion source, the helicon ion source, the multi-cusp RF ion source, and the sputter type RF source of metal ions. A global model and transformer model were applied for calculation of RF source plasma parameters. Ion energy spread, ion mass, and ion current density of some sources were measured in the wide range of RF power, extraction voltage and gas pres-sure. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3555

New Standards of Quality Management in Audit. The Risk-Based Approach

The article proves that auditing is a socially significant activity. Therefore, the auditor must ensure the validity of his opinion, which is achieved through ensuring the quality of audit procedures at all stages. Failure to ensure the quality of audit tasks is a reason to mislead users of financial statements of enterprises and auditorsʼ conclusions, does not warn users about financial problems and the possibility of bankruptcy, especially in socially significant companies. From December 2022 on the audit, quality control of audit services are waiting for radical changes in quality management. The article highlights the results of a study devoted to new requirements to quality management in auditing firms, resulting from the enforcement of the new standards: ISQM 1 “Quality Management”, ISQM 2 “Engagement Quality Reviews”, and the revised ISA 220 “Quality Management for an Audit of Financial Statements”. The design of a quality management system at firm level is considered in ISQM 1, including building up an organization system for management of audit quality, creating the essential conditions for performing audits. This standard will be enforced in place of the existing ISQC 1“Quality Control for Firms that Perform Audits and Reviews of Financial Statements, and Other Assurance and Related Services Engagements”. The new quality management system includes the following components: the risk assessment process of the audit firm; management and leadership, ethical requirements, acceptance, continuation of customer relationships and specific tasks; resource; performance of tasks; information and communication; monitoring and sanctions. ISQM 2 “Engagement Quality Reviews” specifies the requirements to reviewers of the quality of performed audit engagements. A quality reviewer is required to have knowledge and understanding of professional standards, current legal and normative acts, and understanding of firm’s policies or procedures used in the process of engagement performance; knowledge of the industry of a company to which audit services on engagement performance were provided; the professional experience in evaluations of scopes and complexity of the performed engagements, the professional qualification for quality evaluations of the engagement performance, including the firm’s obligation for providing this qualification. The abovementioned requirements cause the need in additional studies aimed at elaborating new schemes for actions and inclusion of engagements in job descriptions of quality reviewers

Properties of ZnO/ZnAl2_2O4_4 composite PEO coatings on zinc

Recently the successful formation of PEO coatings on zinc in a phosphate aluminate electrolyte was shown. The produced composite coatings contain various mixtures of ZnO and ZnAl$_2$O$_4$. In frame of the current study, the properties of the formed coatings including adhesion/cohesion, wear, corrosion and photocatalytic activity were analysed to identify possible applications. However, the coatings show internal porosity and a sponge-like structure. Thus the cohesion within the coating is quite low. Pull-off tests have demonstrated clear rupture within the PEO layer at strength values as low as 1 MPa. The photocatalytic activity is limited, in spite of the formation of a higher amount of ZnO at shorter treatment times. Interestingly, the composite coatings of ZnO and higher amounts of ZnAl$_2$O$_4$ spinel showed a higher activity, but not sufficient for fast and effective catalytic cleaning applications

Методика розрахунку циліндричної ультразвукової кавітаційної камери фільтра з ефектом регенерації

Introduction. The creation of modern ultrasonic cavitation equipment for filtering working fluids in various technological processes is associated with the study of the interaction of a liquid load with ultrasonic emitters, taking into account the influence of the geometric shape of the cavitation chamber. The efficiency of the operation of ultrasonic cavitation devices for filtration is a rather urgent issue today and directly depends on the quality of this agreement. Problem statement. To build an ultrasonic filter with a regeneration effect and to increase its efficiency, it is necessary to create a calculation method that will take into account both the impedance of electro-acoustic emitters and the complexity of the geometric shape of the cavitation chamber. Development of calculation methods. The proposed method for calculating the geometric dimensions of the acoustic resonance system of the modular section of the tubular ultrasonic cavitator, which is excited by folded piezoelectric drive-emitters, which carry out longitudinal vibrations and are installed on the outer surface of the tubular vibrator. Simulation results. The results of modeling in the Abaqus Student Edition 2018 software environment are presented, confirming the possibility of creating ultrasonic flow cavitators, the vibrator, which are excited in a radial-flexion mode of vibration, for the technological process of ultrasonic cavitation filtration with the regeneration effect. Conclusions. The proposed calculation technique allows designing cylindrical ultrasonic cavitation filter chambers with a regeneration effect. Repeated practical verification of the presented method for calculating resonant acoustic systems has confirmed its sufficient accuracy under the applied assumptions.Введение. Создание современного ультразвукового кавитационного оборудования для фильтрования рабочих жидкостей в различных технологических процессах, связано с изучением вопросов взаимодействия жидкостной нагрузки с ультразвуковыми излучателями с учетом влияния геометрической формы кавитационной камеры. Их согласование напрямую влияет на эффективность работы ультразвуковых кавитационных устройств для фильтрации и является достаточно актуальным вопросом на сегодня. Постановка задачи. Для построения ультразвукового фильтра с эффектом регенерации и для повышения его эффективности необходимо создать методику расчета, которая будет учитывать как импеданс электроакустических излучателей, так и сложность геометрической формы кавитационной камеры. Разработка методики расчета. Предложена методика расчета геометрических размеров акустической резонансной системы модульной секции трубчатого ультразвукового кавитатора, что возбуждается сложенными пьезоэлектрическими приводами-излучателями, которые осуществляют продольные колебания и установлены на внешней поверхности трубчатого вибратора. Результаты моделирования. Представлены результаты моделирования в программной среде Abaqus Student Edition 2018, подтверждающие возможность создания ультразвуковых проточных кавитаторов, вибраторы которых возбуждаются на радиально-сгибательной моде колебаний, для технологического процесса ультразвуковой кавитационной фильтрования с эффектом регенерации. Выводы. Предложенная методика расчета позволяет проектировать цилиндрические ультразвуковые кавитационные камеры фильтра с эффектом регенерации. Многократная практическая проверка представленной методики расчета резонансных акустических систем подтвердила ее достаточную точность при примененных предположений.Розглянуті питання розрахунку ультразвукових проточних кавітаторів з циліндричним трубчастим вібратором, для створення систем ультразвукового кавітаційного фільтрування з ефектом регенерації фільтрувального елементу. Запропонована методика розрахунку геометричних розмірів акустичної резонансної системи модульної секції трубчастого ультразвукового кавітатора, що збуджується складеними п’єзоелектричними приводами-випромінювачами, які здійснюють поздовжні коливання і встановлені на зовнішній поверхні трубчастого вібратора. Представлені результати моделювання, які підтверджують можливість створення ультразвукових проточних кавітаторів, вібратор яких збуджується на радіально-згинальній моді коливань, для технологічного процесу ультразвукового кавітаційного фільтрування з ефектом регенерації

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum