552 research outputs found
Трансфокаторы для операций лазерной обработки в полиграфии
Пропонуються оригінальні схеми і конструкції об’єктивів із змінною фокусною відстанню та методики їх розрахунку для розширення можливостей лазерної обробки при виготовленні форм для друку.Original charts and constructions of lenses with variable focal distance, methods of their calculation for enhancement of laser treatment at making of forms for a print are offered.Предлагаются оригинальные схемы и конструкции объективов с переменным фокусным расстоянием, методики их расчета для расширения возможностей лазерной обработки при изготовлении форм для печати
Технология и оборудование для очистки печатных форм
У статті досліджена можливість використання відомих методів поверхневого очищення виробів від бруду, оксидів, плівок в операціях видалення залишків фарби на органічній і мінеральній основі з робочих поверхонь друкарських форм, виготовлених з різних матеріалів. Встановлено, що найбільш відповідним методом є очищення поверхні променем лазера. Проте, необхідність збереження вихідної тонкої структури рельєфу поверхні форми і різноманітність матеріалів для її виготовлення (метали, пластмаси, гума, а також багатошарові системи) ускладнюють технологічне забезпечення операцій очищення. Всупереч відомій мотивації їх побудови в статті пропонується інший підхід до вибору типу лазера (за довжиною хвилі і режиму генерації) залежно від поєднання складу бруду і матеріалу форми для забезпечення об’ємного характеру нагрівання шару, що видаляється, незалежно від вибраного механізму його руйнування. Розроблені операції технологічно забезпечені. Запропонований алгоритм вибору технологічного регламенту операції, склад і комплектація устаткування, а також матеріальний план модернізації стандартних комплектуючих лазерної установки, призначеної для виконання широкого класу операцій.In the article possibility of application of the known wares superficial cleaning methods from dirt, oxides, tapes is studied for use in the operations of ink tailings delete from the workings surfaces of printing forms, made from different materials. It is set that the most a suitable method is surface cleaning by the laser ray. However, the necessity of initial coarse-fine maintenance of form surface relief and variety of materials for its making (metals, plastics, rubber, and also multi-layered systems) complicate the cleaning operations technological providing. Despite the known their construction motivation in the article other going is offered new view of laser selection (on a wave-length and mode of generation) depending on combination of dirt composition and form material for providing of volume heating character of the deleted layer regardless of the chosen his destruction mechanism. The developed operations are technologically well-to-do. The technological operation regulation choice algorithm, composition and equipment acquisition, and also financial plan of standard puts of the laser setting modernization, intended for implementation of wide operations class, are offered.В статье исследована возможность применения известных методов поверхностной очистки изделий от грязи, окислов, пленок в операциях удаления остатков краски на органической и минеральной основе с рабочих поверхностей печатных форм, изготовленных из разных материалов. Установлено, что наиболее подходящим методом является очистка поверхности лучом лазера. Однако, необходимость сохранения исходной тонкой структуры рельефа поверхности формы и разнообразие материалов для ее изготовления (металлы, пластмассы, резина, а также многослойные системы) усложняют технологическое обеспечение операций очистки. Вопреки известной мотивации их построения в статье предлагается иной подход к выбору типа лазера (по длине волны и режиму генерации) в зависимости от сочетания состава грязи и материала формы для обеспечения объемного характера нагрева удаляемого слоя независимо от выбранного механизма его разрушения. Разработанные операции технологически обеспечены. Предложен алгоритм выбора технологического регламента операции, состав и комплектация оборудования, а также материальный план модернизации стандартных комплектующих лазерной установки, предназначенной для выполнения широкого класса операций
Технологическое обеспечение операций лазерной технологии в полиграфии
Для відомих та нових видів лазерної обробки при виготовленні поліграфічної продукції запропоновано методики вибору режимів обробки для різних технологічних схем формоутворення та їх інформаційне забезпечення.For the known and new types of laser machining at making of graphic art the methods of machining modes choice for the different flowsheets of forming and them informative providing are offered.Для известных и новых видов лазерной обработки при изготовлении полиграфической продукции предложены методики выбора режимов обработки для разных технологических схем формообразования и их информационное обеспечение
Результаты исследований нового метода для метрологического обеспечения измерений массы на конвейерных весах
The paper considers the issue related to calibration of conveyor weigher in laboratory environment for its usage as etalon and the subsequent transfer of a unit of linear density from them to the transported means of comparison – the measure of linear density. The equations of the mass flow in instant hopper-conveyor system are got. The algorithm of etalon conveyor weigher calibration is developed on the results of mass measurement in hopper at work process of hopper-conveyor instant system which doesn’t require passing a known fixed mass through a conveyor weigher. The transfer way of linear density unit from etalon conveyor weigher to linear density measure with accuracy required by measurement chain is proposed.В статье рассматривается способ калибровки конвейерных весов в лабораторных условиях для использования их в качестве эталонных и последующей передачи от них единицы линейной плотности транспортируемому средству сравнения – мере линейной плотности. Получены уравнения для описания потока масс в замкнутой системе бункер – конвейер. Разработан алгоритм калибровки эталонных конвейерных весов по результатам измерения массы в бункере в процессе работы замкнутой системы бункер – конвейер, не требующий пропускания через конвейерные весы известной фиксированной массы. Предложен способ передачи от эталонных конвейерных весов единицы линейной плотности мере линейной плотности с требуемой поверочной схемой точностью
Relationships Linking Amplification Level to Gene Over-Expression in Gliomas
Background: Gene amplification is thought to promote over-expression of genes favouring tumour development. Because amplified regions are usually megabase-long, amplification often concerns numerous syntenic or non-syntenic genes, among which only a subset is over-expressed. The rationale for these differences remains poorly understood. Methodology/Principal Finding: To address this question, we used quantitative RT-PCR to determine the expression level of a series of co-amplified genes in five xenografted and one fresh human gliomas. These gliomas were chosen because we have previously characterised in detail the genetic content of their amplicons. In all the cases, the amplified sequences lie on extra-chromosomal DNA molecules, as commonly observed in gliomas. We show here that genes transcribed in nonamplified gliomas are over-expressed when amplified, roughly in proportion to their copy number, while non-expressed genes remain inactive. When specific antibodies were available, we also compared protein expression in amplified and nonamplified tumours. We found that protein accumulation barely correlates with the level of mRNA expression in some of these tumours. Conclusions/Significance: Here we show that the tissue-specific pattern of gene expression is maintained upon amplification in gliomas. Our study relies on a single type of tumour and a limited number of cases. However, it strongly suggests that, even when amplified, genes that are normally silent in a given cell type play no role in tumour progression
Characterizing the initial conditions of heavy-ion collisions at the LHC with mean transverse momentum and anisotropic flow correlations
Correlations between mean transverse momentum and anisotropic flow coefficients or are measured as a function of centrality in Pb–Pb and Xe–Xe collisions at sqrt(sNN) = 5.02 TeV and 5.44 TeV, respectively, with ALICE. In addition, the recently proposed higher-order correlation between [pt], v2, and v3 is measured for the first time, which shows an anticorrelation for the presented centrality ranges. These measurements are compared with hydrodynamic calculations using IP-Glasma and TRENTO initial-state shapes, the former based on the Color Glass Condensate effective theory with gluon saturation, and the latter a parameterized model with nucleons as the relevant degrees of freedom. The data are better described by the IP-Glasma rather than the TRENTO based calculations. In particular, Trajectum and JETSCAPE predictions, both based on the TRENTO initial state model but with different parameter settings, fail to describe the measurements. As the correlations between [pt] and vn are mainly driven by the correlations of the size and the shape of the system in the initial state, these new studies pave a novel way to characterize the initial state and help pin down the uncertainty of the extracted properties of the quark–gluon plasma recreated in relativistic heavy-ion collisions
General balance functions of identified charged hadron pairs of (pi,K,p) in Pb-Pb collisions at 2.76 TeV
First measurements of balance functions (BFs) of all combinations of identified charged hadron ( π , K, p)
pairs in Pb–Pb collisions at √sNN = 2.76 TeV recorded by the ALICE detector are presented. The BF
measurements are carried out as two-dimensional differential correlators versus the relative rapidity
(delta-y) and azimuthal angle (delta-φ) of hadron pairs, and studied as a function of collision centrality. The delta-φ
dependence of BFs is expected to be sensitive to the light quark diffusivity in the quark–gluon plasma.
While the BF azimuthal widths of all pairs substantially decrease from peripheral to central collisions, the
longitudinal widths exhibit mixed behaviors: BFs of π π and cross-species pairs narrow significantly in
more central collisions, whereas those of KK and pp are found to be independent of collision centrality.
This dichotomy is qualitatively consistent with the presence of strong radial flow effects and the existence
of two stages of quark production in relativistic heavy-ion collisions. Finally, the first measurements of
the collision centrality evolution of BF integrals are presented, with the observation that charge balancing
fractions are nearly independent of collision centrality in Pb–Pb collisions. Overall, the results presented
provide new and challenging constraints for theoretical models of hadron production and transport in
relativistic heavy-ion collisions
Measurement of the production of (anti)nuclei in p–Pb collisions at sNN=8.16TeV
Measurements of (anti)proton, (anti)deuteron, and (anti)3He production in the rapidity range -1 > y > 0 as a function of the transverse momentum and event multiplicity in p–Pb collisions at a center-of-mass energy per nucleon–nucleon pair sqrt(sNN) = 8.16 TeV are presented. The coalescence parameters B2 and B3, measured as a function of the transverse momentum per nucleon and of the mean charged-particle multiplicity density, confirm a smooth evolution from low to high multiplicity across different collision systems and energies. The ratios between (anti)deuteron and (anti)3He yields and those of (anti)protons are also reported as a function of the mean charged-particle multiplicity density. A comparison with the predictions of the statistical hadronization and coalescence models for different collision systems and center-of-mass energies favors the coalescence description for the deuteron-to-proton yield ratio with respect to the canonical statistical model
Hypertriton Production in p-Pb Collisions at √sNN = 5.02 TeV
The study of nuclei and antinuclei production has proven to be a powerful
tool to investigate the formation mechanism of loosely bound states in
high-energy hadronic collisions. The first measurement of the production of
in p-Pb collisions at = 5.02
TeV is presented in this Letter. Its production yield measured in the rapidity
interval -1 < y < 0 for the 40% highest multiplicity p-Pb collisions is . The measurement is compared with the expectations of statistical
hadronisation and coalescence models, which describe the nucleosynthesis in
hadronic collisions. These two models predict very different yields of the
hypertriton in small collision systems such as p-Pb and therefore the
measurement of is crucial to distinguish between them.
The precision of this measurement leads to the exclusion with a significance
larger than 6 of some configurations of the statistical hadronisation,
thus constraining the production mechanism of loosely bound states
Forward rapidity J/ψ production as a function of charged-particle multiplicity in pp collisions at = 5.02 and 13 TeV
The production of J/ψ is measured as a function of charged-particle multiplicity at forward rapidity in proton-proton (pp) collisions at center-of-mass energies √s = 5.02 and 13 TeV. The J/ψ mesons are reconstructed via their decay into dimuons in the rapidity interval (2.5 < y < 4.0), whereas the charged-particle multiplicity density (dNch/dη) is measured at midrapidity (|η| < 1). The production rate as a function of multiplicity
is reported as the ratio of the yield in a given multiplicity interval to the multiplicity-integrated one. This observable shows a linear increase with charged-particle multiplicity normalized to the corresponding average value for inelastic events (dNch/dη/〈dNch/dη〉),
at both the colliding energies. Measurements are compared with available ALICE results at midrapidity and theoretical model calculations. First measurement of the mean transverse momentum (〈pT〉) of J/ψ in pp collisions exhibits an increasing trend as a function
of dNch/dη/〈dNch/dη〉 showing a saturation towards high charged-particle multiplicities
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