bluuebunny/crossref_metadata_2025 huggingface dataset:
Сведения о Шихаб ад-Дине ал-Марджани в дагестанских рукописях в контексте дискуссий об иджтихаде в первой трети ХХ в.
Authors: Shikhaliev Shamil
Published: November 2019

The article is devoted to the references to the Tatar scholar Shihabaddin Mardjani in the Dagestani Arabic-script manuscripts written in the first third of the 20th century. Daghestani scholars noted the important role of Mardjani and his works in the intellectual history of Islam. For this reason, they travelled to Kazan to get an acquaintance with him and copied his works. Dagestani scholars wrote reviews on his works as well as dedicated poems to Mardjani himself. Later, the name Mardjani entered the Dagestani legal tradition in the framework of debates on taqlid and ijtihad. Along with classical Arab scholars, the name of Mardjani has been often referred in Daghestani manuscripts on the theory of Muslim Law. Althoug Dagestani Muslim jurists held different views on issues of taqlid and ijtihad, each of them interpreted the ideas of Mardjani on Islamic legal issues in his own way. Regardless of their preferences in the matters of theory of Islamic law, Dagestani scholars highly valued the authority of Mardjani as a one of the major scholars in the Islamic World.
Shihabaddin Mardjani and the Muslim Archive in Russia
Authors: Bustanov Alfrid
Published: November 2019

Shihabaddin Mardjani (1818-1889) was one of the first Muslim scholars in the Russian empire to approach conceptually the challenge of Russian imperial scholarship (Kemper, 1998, pp. 462-465). Despite his readiness to speak to audiences beyond the circles of Muslim elites (for example, by participating in the scholarly proceedings at Kazan University), Mardjani largely remained in the confines of Islamic tradition with its specific approaches to the production of knowledge. As the library of Mardjani either have been lost in fire or dispersed in many private collections, his works in the manuscript and published form remain the main source of analysis for historians of today. Still, there are documents from the personal archive of Mardjani that allow us to judge about the nature of his approach to remnants of the past, i.e. his view on the Muslim concept of legacy.
Рукописное наследие татарских ученых в фондах Института востоковедения Академии Наук Республики Узбекистан
Authors: Mukhammadaminov Saidakbar
Published: November 2019

The article is dedicated to the manuscript heritage of Tatar scholars held in Abu Rayhan Beruni Institute of Oriental Studies of the Academy of Sciences of Uzbekistan, one of the richest manuscript repositories in the world. Works of manuscripts of Tatar theologians such as Abdurahim Utyz-Imyani, Abu al-Nasr Qursawi, Shihabaddin Mardjani, and Hisam al-Din b. Sharaf al- Din al-Bulgari, Kamal al-Din b. Siraj al-Din al-Uribfori al-Kazani, ̒Ayn al-Din b. Jalal al-Din al-Kazani, Abu al-Sharaf Husain b. Abu Umar al- Bulgari, Muhammad Latif b. Abdulislam al-Bulgari are analyzed. Based on a review of the manuscripts, it is established that some of them have not yet been catalogued. It is argued that the works of Tatar scholars were mainly devoted to religious subjects. The role of Tatar scholars in the creation of commentaries and works on legal, medical and Sufi terms is analyzed in order to make the works accessible to a wide range of people seeking knowledge.
Confiabilidade de métodos de previsão da capacidade de carga de estacas a partir de resultados de CPT
Authors: José Giacon Junior Admir , Padovezi Rocha Breno , Brito Fernandes Jeferson , Nogueira Gorla , Luiz Giacheti Heraldo
Published: November 2019

Este artigo apresenta uma análise da confiabilidade de três métodos semi-empíricos de previsão da capacidade de carga de estacas a partir do FORM (First Order Reliability Method), com o objetivo de avaliar a probabilidade que tais métodos têm de estimar a capacidade de carga contra a segurança. Nesse estudo foram considerados resultados de 25 ensaios CPT realizados em um único local e o resultado de uma prova de carga em uma estaca escavada de 0,25 m de diâmetro e 8 m de comprimento, instalada em um solo tropical arenoso não saturado que ocorre na cidade de Bauru, interior de São Paulo. As distribuições das variáveis aleatórias definidas pelas resistências de ponta (qc) e de atrito lateral (fs) medidas com o CPT, bem como as parcelas de resistência de ponta (Qp,ult) e de atrito lateral (Ql,ult) da estaca se adequaram a uma distribuição normal de probabilidades, segundo a aplicação do teste estatístico de Kolmogorov-Smirnov. As análises de confiabilidade apontaram que o método mais indicado para aplicação no caso estudado é aquele proposto por Aoki & Velloso, que apresentou valor de probabilidade de estimativa contra a segurança de 0,16%, enquanto os outros dois métodos só podem ser aplicados após sofrerem ajustes.
Protective effects of N-acetylcysteine and taurine on oxidative stress induced by chronic acetaldehyde administration in rat liver and brain tissues
Authors: YILDIZ Zeynep Dicle , BAKİ Adile Merve , BAŞARAN-KÜÇÜKGERGİN Canan , VURAL Pervin , DOĞRU-ABBASOĞLU Semra , UYSAL Müjdat
Published: November 2019

Aim:
Acetaldehyde (AA) is one of the
main products of alcohol metabolism. Exposure to AA can occur through ingestion
of several dietary products, inhalation of cigarette smoke/automobile exhausts,
or contact with cosmetics. AA accumulation causes oxidative stress. The aim of
this study was to investigate the prooxidant/antioxidant status in rats
chronically exposed to AA, and to evaluate the effects of N-acetylcysteine
(NAC) and taurine (TAU) on prooxidant/antioxidant balance. Methods: Sprague Dawley rats were divided in the
following groups (n=8; each): Control, AA, AA+NAC, AA+TAU. Reactive oxygen
species (ROS), diene conjugate (DC), malondialdehyde (MDA), protein carbonyl
(PC), ferric reducing antioxidant power (FRAP) and glutathione (GSH) levels as
well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities
were determined in liver and brain tissues. Results: AA treatment in drinking water
was detected to induce prooxidant state in both liver and brain of rats. NAC
treatment decreased AA-induced prooxidant status in both tissues. Although TAU
treatment diminished ROS levels, MDA and PC levels remained unchanged in examined
tissues of AA-treated rats. NAC and TAU elevated liver and brain GSH levels in
AA-treated rats.

Conclusion:
Chronic AA administration has created a
prooxidant condition, and NAC/TAU appears
to be useful in suppression of the developed oxidative stress.
Does the measurement of the size of the first trimester subchorionic hematoma by 2D and 3D ultrasonographic techniques have any effect on adverse pregnancy outcomes?
Authors: ÖZLER Sibel , GÜMÜŞ GÜLER Başak
Published: November 2019

Aim: We aimed to evaluate whether the measurement of subchorionic
hematoma (SCH) size with 2D and 3D ultrasonography affects adverse pregnancy
outcomes. Methods: One hundred fifty-eight pregnant patients having SCH were
enrolled in the study. The diagnosis of SCH was made by 2D and 3D
ultra-sonographic methods in the first trimester, between 6th and 14th
gestational weeks. Patients having SCH were determined with adverse pregnancy
outcomes such as miscarriage, intrauterine fetal death (IUFD), and preterm
labor (PL). Logistic regression analyses were applied for the relationship of miscarriage,
IUFD, PL, and SCH. Results: There were no statistically significant differences for body
mass index, 2-D hematoma sizes, 3-D hematoma sizes, and pregnancy outcomes
between the groups. Miscarriage/IUFD rate was 4.6%, PL rate was 6.9%, and the
term delivery rate was 88.5% in the primiparas having SCH. Miscarriage/IUFD
rate was 7%, PL rate was 3.5%, and the term delivery rate was 89.5% in the
multiparas having SCH. No significant association was observed between 2D and
3D hematoma sizes and IUFD and PL. In the logistic regression model, SCH ≥ 500
cm3 was found to be a risk factor associated with PL, not regarding
the measurement technique (OR:1.008, 95% CI: 1.002-1.012, p=0.006).

Conclusion: We determined that SCH size increases the
risk of PL. We observed no effect of diagnosis and follow-up of SCH, by 2D and
3D ultrasonography techniques on adverse pregnancy outcomes such as
miscarriage, IUFD, and PL.
Successful management of lower rectal carcinoma recurrence on perineal pseudo-continent colostomy: a case report and review of literature
Authors: BOUHANİ Malek , JAİDANE Olfa , BOUİDA Mohamed Amine , BENNACEUR Radhi , CHARGUİ Riadh , RAHAL Khaled
Published: November 2019

Recurrence of lower rectal carcinoma on perineal pseudo-continent colostomy is rarely reported in the literature. It presents a real challenge for the physician. The aim of this case report was to document an exceptional recurrence and how to manage it.  A 56-year-old man presented with stage II adenocarcinoma of the lower rectum. He received concomitant chemoradiation followed by abdominoperineal resection with perineal pseudo-continent colostomy. Three years later, he developed a local recurrence of his prior adenocarcinoma, on the perineal pseudo-continent colostomy. He underwent wide excision, followed by reconstruction with a rectus abdominis myocutaneous flap with an inferior pedicle and an oblique skin paddle. He underwent adjuvant chemotherapy. The patient is free of disease with three years follow up. Extended resection should be considered as an initial treatment for locally recurrent rectal cancer.
Mapping Challenges of the Romanian NGOs. A Focus on Human Resources
Authors: Zbuchea Alexandra , Ivan Loredana , Stan Sergiu-Octavian , Dămăşaru Costin
Published: November 2019

The effectiveness of NGOs, similar to other types of organizations, depends on the quality and implication of their employees and volunteers. The literature highlights the role of learning capabilities, organizational learning, networking and community capacity building in ensuring organizational sustainable development in the NGO sector. In this framework, professional human resources should be an important part of the management strategy. Continuous and personalized training would be also important for NGOs. The present paper presents a qualitative investigation aiming to map the training needs and practices of the NGO sector in Romania, both from the perspective of its representatives and its stakeholders. The findings show a general agreement and concern related to the professionalism of the workers in the sector, as well as related to the lack of explicit responsibility/the feeling of being accountable assumed by the members of the sector. The study also revealed a need for closer cooperation between the members of the Quadruple Helix.
System Dynamics Approaches in Managing Real Estate Development Crises: Conceptual versus Scenario-Based
Authors: Abdel-Latif Amr , Saad-Eldien Ahmed , Marzouk Mohamed
Published: November 2019

Real Estate development organizations are vulnerable to crises' events due to the complexity of the external environment, internal structure, and operation systems. This paper aims to present, analyze, and compare between two proposed approaches for managing development crises based on system dynamics methodology. Twenty crises' scenarios are identified in order to be utilized in the analysis process of two approaches. These approaches are the conceptual approach and the scenario-based approach. The conceptual approach provides a framework to manage crises in a broad manner using Mitroff's model. The scenario-based approach uses crisis event characteristics to specify its containment policy. The crises' characteristics are identified by analyzing courses with time, classifying attributes, and specifying archetypes. The outcome of the analysis process for both approaches should guide developers and upgrade the quality of their decision in selecting adequate containment policies.
Identifying Key Factors Affecting Customer’s Decision-Making of Internet Service Providers in Albania
Authors: Buhaljoti Ana
Published: November 2019

The internet market in Albania is expanding and new Internet service providers have grown significantly. Improving competition in this market relies on understanding why customers choose a particular service provider. This research paper aims to investigate and understand how a range of factors impact the customers’ perceptions to choose their internet service provider. It explores the factors affecting customer’s decision by using a quantitative method via a questionnaire survey. For identifying behavioral factors, a survey was conducted face to face. The structured questionnaire assessed the users’ perceptions and opinions in choosing an internet provider. The target population consisted of individual internet users at the household level who have fixed internet access at home. This paper presents the variables that influence consumers purchase decision by reviewing key factors in the sector and identifies consumer patterns in purchasing Internet Service Provider (ISPs). The findings of the research showed that brand image is the most influential factor in the selection of ISPs. In order to gain new customers, internet providers have to take into consideration the company’s image as a critical factor to the consumer decision-making, followed by the information disposed to customers and the risk associated to the service provider. The research provided high-speed internet providers in Albania insights on how to gain new customers and enhance competitiveness
Калмыцкая терминология родства как отражение исторических связей и этнокультурных контактов Ойратского мира и тувинцев
Authors: Popov Vladimir A. , Burykin Aleksey A.
Published: November 2019

Статья представляет собой обобщающую работу, посвященную выявлению специфики системы терминов родства калмыков как лексической микросистемы в отношении распределения составляющих ее отдельных номинационных единиц, а также тех семантических признаков, которые формируют лексические оппозиции внутри этой системы и определяют ее историко-типологическую динамику, в сравнении с системой терминов родства тувинцев. Объясняются причины сходств и различий между терминологиями родства монголоязычных (в частности, ойратских) и тюркоязычных народов на примере номенклатур родства калмыков и тувинцев, а также рассматривается взаимодействие терминов родства и свойства тюркского и монгольского происхождения у тувинцев.Отмечается, что объяснение наблюдаемых лексических сходств тюркских и монгольских языков исключительно как контактных явлений в свете фактов истории самих тюркских языков имеет на несколько порядков меньшую вероятность, чем объяснение тех же сходств как следствие генетического родства алтайских языков при наличии в них некоторого количества перекрестных заимствований. Терминология родства тувинцев-эрзинцев носит отчетливые следы языковых контактов с монголами-ойратами. Для системы терминов родства калмыков характерны строгая соотнесенность терминов родства по признаку пола как по восходящей, так и по нисходящей линиям, наличие особой лексической единицы для номинации родственников по материнской стороне, счет родства до 9-го поколения как по восходящей, так и по нисходящей линиям, тогда как у других монголоязычных народов учитывается счет родства только до 5-го  поколения по восходящей и 4-го поколения по нисходящей линиям.
Современная этническая идентичность ойратов и тувинцев Китая: к вопросу о специфике национального вопроса в КНР
Authors: Бакаева Эльза Петровна , Юша Жанна Монгеевна
Published: November 2019

Статья посвящена освещению специфики национального вопроса в Китайской Народной Республике на примере ойратов и тувинцев. Авторы показывают сложный состав монгольских народов Китая, приводят данные по истории их изучения в 1950-е гг., когда в КНР происходил этап становления национальной политики, решались вопросы национально-языкового строительства и реализовывался проект этнической классификации.Учет состава населения КНР, сложившийся с периода 1956–1976 гг., затронул все стороны жизни китайского общества, в том числе проблему национального состава. В первой половине 1950-х гг. проводились исследования в области этнографии неханьских народов и языков национальных меньшинств КНР. Несмотря на это был принят принцип объединения народов, направленный на реализацию политики их слияния. Ряд монголоязычных народов, а также и тюркоязычные тувинцы были официально включены в понятие «монголы».Сегодня в КНР проводится иная национальная политика. Но тезис о 56 национальностях КНР продолжает бытовать. Принимая необходимость официальной монгольской идентичности, представители ойратов и тувинцев тем не менее сохраняют свою этническую идентичность.
Ойратская рукопись «Хридая-дхарани Матерей» (ойр. ekeyin zürken tarni orošiboi) из фонда Национального музея Тувы
Authors: Gedeeva Darina B. , Mirzaeva Saglara V.
Published: November 2019

В статье вводится в научный оборот текст ойратской рукописи «Ekeyin zürken tarni orošiboi» (‘Хридая-дхарани Матерей’). Текст хранится в коллекции Национального музея Республики Тыва под инвентарным номером М-835. Анализ монгольских и ойратских письменных памятников необходим для исследования истории духовной культуры монгольских народов, а также тюркских этносов, находившихся в едином с ними культурном ареале. Данная статья относится к ряду научных публикаций, отражающих исторические и этнокультурные связи монголо-ойратского мира с тувинским. Несомненно, один из ключевых объединяющих факторов — это буддизм. Приводится анализ содержания рукописи, которая включает в себя несколько коротких текстов дхарани из известного ритуального сборника «Сундуй».Дается транслитерация ойратского рукописного текста, снабженная параллельным переводом на русский язык.
Ойратская рукопись сутры «Собрание благоприятствования» (ойр. Ölzöi dabxurlaqsan) из тувинского архива
Authors: Mirzaeva Saglara V.
Published: November 2019

Статья вводит в научный оборот текст ойратской рукописи «Xutuqtu ölzöi dabxurlaqsan kemēkü yeke kölgöni sudur oršibo» (‘Высшая сутра Махаяны «Собрание благоприятствования»’). Она хранится в коллекции Национального музея Республики Тыва под инвентарным номером М-776.Предположительно рукопись попала в коллекцию музея, как и многие другие буддийские тексты на монгольском и ойратском письме, из буддийских монастырей, функционировавших прежде на территории Тувы, или из частных коллекций.В колофоне указано, что сутра была переведена Зая-пандитой Намкай Джамцо. Дается краткое описание роли памятника в тибето-монгольской литературной традиции и его функционирования в буддийских ритуалах. Приводится транслитерация ойратского рукописного текста, снабженная параллельным переводом на русский язык.
O uso do sistema de segurança cruzado como ferramenta para notificação de incidente: um relato de experiência
Authors: Pinheiro Leisson Domingues , Reyes Paola Alejandra Valenzuela , Lobão Gal Caroline Alho
Published: November 2019

Objetivo: O estudo propõe implementar provas com o Safety Cross System como ferramenta inovadora para notificação de incidente. Relato de Experiência: Este estudo constitui um relato de experiência de caráter descritivo de um Centro integrado de inclusão e reabilitação do estado do Pará em relação a implementação de evidências em um sistema de notificação de incidentes que usa um calendário cruzado para registrar as notificações de incidentes permite uma metodologia visual para gerenciar a segurança do paciente de forma transparente, ou seja, o processo registra notificações de incidentes com cores diferentes para cada classificação. Considerações Finais: Algumas instituições adotam diferentes sistemas para melhorar os índices de notificações de incidente. O calendário cruzado é um sistema atraente, a equipe sente-se mais confortável em fazer parte do processo de notificação e análise, propondo melhorias de forma democrática aos processos de segurança do paciente.
Modeling Structure and Absorption Spectra of the Bacteriophytochrome-Based Fluorescent Protein IFP1.4
Authors: Polyakov Igor , Grigorenko Bella , Nemukhin Alexander
Published: November 2019

We report the results of quantum mechanics/molecular mechanics (QM/MM) simulations of structures and absorption spectra of the fluorescent protein IFP1.4 engineered from the chromophore-binding domain of Deinococcus radiodurans (DrCBD). In this work, we focus on different protonation states of the biliverdin chromophore in the red-absorbing form of the protein. To this goal, the protein with the all-protonated chromophore as well as the structures obtained by removal of protons from the biliverdin pyrrole rings to a suitable acceptor within the system are considered. Several quantum chemistry methods to compute the S0→S1 excitation energies are used in the QM part to estimate shifts in the absorption band maxima upon chromophore deprotonation.
Architecture of Allosteric Structure. Demonstration of the Fundamental Element of Allosteric Structure of Human Hemoglobin. O2-Equilibrium Binding Curve of Purified Human Hemoglobin in an Effector-Free Supporting Electrolyte.
Authors: Knowles Francis
Published: November 2019

The O2-affinity of human hemoglobin, free of effector molecules, was measured in 0.050 M BisTris, pH 7.0 with HCl, 20oC. A Hill plot of O2-equilibrium binding data reveals an initial slope of 2 and fails to demonstrate an upward inflection. The tetrameric hemoglobin structure in an effector-free supporting electrolyte can be described as two cooperative dimeric subunits. Equilibrium constants of these steps are related to intrinsic O2-binding constants for alpha and beta-chains, K(alpha) and K(beta). The equation of state is comprised of four unknown quantities. O2-Binding constants are not expected to be identical for each of the dimeric cooperative subunits. The first cooperative subunit binds O2 while bound to the second O2-free cooperative dimer. The second cooperative dimer binds O2 while bound to a fully oxygenated cooperative dimer. Effecter-free human hemoglobin is half saturated with1.9 micromolar oxygen. Addition of 0.1 M NaCl to the supporting electrolyte results in an approximately 4-fold increase in the concentration of O2 required for half saturation of hemoglobin, 8.1 micromolar oxygen. The mechanism of the response to chloride ions is attributed to neutralization of positively charged residues in the central cavity of Hb4 by the relatively high concentration of chloride ions.
Design of AIEgens for Near-Infrared IIb Imaging Through Structural Modulation at Molecular and Morphological Levels
Authors: li yuanyuan , Cai Zhaochong , liu shunjie , Zhang Haoke , Wong sherman , Lam Jacky W. Y. , Tsz Kin Kwok Ryan , Qian Jun , Tang Ben Zhong
Published: November 2019

Fluorescence imaging in near-infrared IIb (NIR-IIb, 1500-1700 nm) spectrum holds a considerable promise for tissue imaging with deep penetration and high spatial resolution owing to the minimized autofluorescence and suppressed photon scattering. While few inorganic NIR-IIb fluorescent probes have been reported, their organic counterparts are still underdeveloped, possibly due to the lack of efficient materials with long emission wavelength. Herein, we propose a new molecular design philosophy to develop organic NIR-IIb fluorophores with high quantum yield (QY) by manipulation of the effects of twisted intramolecular charge transfer and aggregation-induced emission at the molecular and morphological levels. A pure organic fluorescent dye emitting up to 1600 nm with a QY of 14.2% in the NIR-II region (1000-1600 nm) is developed. For the first time, NIR-IIb fluorescence imaging of blood vessels and deeply-located intestinal tract of live mice based on organic dyes is achieved. The results show that organic fluorophore performs superb imaging ability in both superficial blood vessels and internal organs with high resolution and enhanced signal-to-background ratio in NIR-IIb region. We hope this groundbreakingly study will inspire further research on the evolution of pure organic NIR-IIb probes for in vivo imaging.
Light- and Temperature-Assisted Spin State Annealing: Accessing the Hidden Multistability
Authors: Chen Yan-Cong , Meng Yan , Tuček Jiří , Dong Yan-Jie , Song Xiao-Wei , Huang Guo-Zhang , Zhang Chuan-Lei , Ni Zhao-Ping , Zbořil Radek , Tong Ming-Liang
Published: November 2019

Among the responsive multistable materials, spin crossover (SCO) systems are of particular interest for stabilizing multiple spin states with various stimulus inputs and physical outputs. Here in a 2D Hofmann-type coordination polymer [Fe(isoq)2{Au(CN)2}2] (isoq = isoquinoline), hidden multistability of the spin state is accessed by introducing an medium-temperature annealing after a light/temperature stimulation. With the combined effort of magnetic, crystallographic and Mössbauer spectral investigation, these distinct spin states are identified and the light- and temperature-assisted transition pathways are clarified. Such excitation-relaxation and trapping-relaxation joint mechanisms, as ingenious interplays between the kinetic and thermodynamic effects, uncover hidden possibilities for the discovery of multistable materials and the development of multistate intelligent devices.
Relative and Absolute Structure Assignments of Alkenes Using Crystalline Osmate Derivatives for X-Ray Analysis
Authors: Burns Alexander S. , dooley Charles , Carlson Paul R. , Ziller Joseph W. , Rychnovsky Scott
Published: November 2019

Osmium tetroxide and TMEDA form stable crystalline adducts with alkenes. The structure of liquid alkenes can be determined through X-ray analysis of these derivatives. Osmium, a heavy atom, facilitates the crystallographic analysis and the determination of the absolute configuration using common Mo X-ray sources. The utility of this method for assigning structures and absolute configurations was demonstrated on a number of unsaturated substrates that include simple alkenes, enones, enol ethers, and silyl enol ethers.
Linear Free Energy Relationships for Transition Metal Complex Chemistry: Opportunity or Pipe Dream?
Authors: Lan Zhenzhuo , Mallikarjun Sharada Shaama
Published: November 2019

We propose a computational framework for developing Taft-like linear free energy relationships to characterize steric effects on the catalytic activity of transition metal complexes. The framework uses the activation strain model and energy decomposition analysis to isolate electronic and geometric effects, and identifies structural descriptors to construct the linear relationship. We demonstrate proof-of-principle for CH activation with enzyme-inspired [Cu2O2]2+ complexes, each coordinated to two identical bidentate diamine N-donors. Electronic effects are largely similar across the chosen systems and geometric effects – quantified by strain energies – are accurately captured by a linear combination of two structural descriptors. A powerful linear free energy relationship emerges that is both transferable to asymmetrically substituted complexes and independent of choice of theory. We outline steps for expanding this approach to create a generalizable Taft framework for inorganic catalyst design.
Insight on the Factors Controlling the Equilibrium of Allylic Azides
Authors: Vallejos Margarita , Labadie Guillermo
Published: November 2019

Several allylic azides with different double bond substitution were studied to understand the factors governing their equilibrium using density functional theory along with quantum theory of atoms in molecules, Non-covalent Interactions and Natural Bond Orbitals approaches. The results showed the hydroxyl group or heteroatoms in allylic azides interact with the molecule through an electrostatic weak interaction in each pair of regioisomers. The equilibrium shifts of substituted allylic azides, compared to non-substituted allylic azides, are not attributed to the presence of specific interactions, such as hydrogen bond. The observed equilibrium shifts stem mainly from the strengthening and weakening of negative hyperconjugative interactions, which is affected by the weak interaction involving the proximal substituent in each regioisomer. A good linear correlation was obtained between the hyperconjugative energies of pC=C→s*Zb interactions and the calculated percentages of secondary azide and tertiary azides in the equilibrium mixture. Also, the effect of aromatic ring substituent was analysed using such approaches. This study not only provides insight into the factor controlling the stabilities of the substituted allylic azides, but also settle the basis to predict the regioisomer predominance in the equilibrium mixture.
Enhanced Li+ Conduction Within Single-Ion Conducting Crosslinked Gel via Reduced Cation-Polymer Interaction
Authors: Ford Hunter O. , Park Bumjun , Jiang Jizhou , Schaefer Jennifer
Published: November 2019

The development of advanced electrolytes compatible with lithium metal and lithium-ion batteries is crucial for meeting ever growing energy storage demands. One such class of materials, single-ion conducting polymer electrolytes (SIPEs), prevents the formation of ion concentration gradients and buildup of anions at the electrode surface, improving performance. One of the ongoing challenges for SIPEs is the development of materials that are conductive enough to compete with liquid electrolytes. Presented herein is a class of gel SIPEs based on crosslinked poly(tetrahydrofuran) diacrylate that present enhanced room temperature conductivities of 3.5 × 10-5 S/cm when gelled with lithium metal relevant 1,3-dioxolane/dimethoxyethane, 2.5 × 10-4 S/cm with carbonate solutions, and approaching 10-3 S/cm with dimethyl sulfoxide. Remarkably, these materials also demonstrate high conductivity at low temperatures, 1.8 × 10-5 S/cm at -20 °C in certain solvents. Most importantly however, when contrasted with identical SIPEs formulated with poly(ethylene glycol) diacrylate, the mechanisms responsible for the enhanced conductivity are elucidated: decreasing Li+-polymer interactions and gel solvent-polymer interactions leads to an increase in Li+ mobility, improving the ionic conductivity. These findings are generalizable to various SIPE chemistries, and can therefore be seen as an additional set of design parameters for developing future high conductivity SIPEs.
Reversible Shifting of a Chemical Equilibrium by Light: The Case of Keto-Enol Tautomerism of a β-Ketoester
Authors: Lvov Andrey , Yadykov Anton , Lyssenko Konstantin , Shirinian Valerii , Khusniyarov Marat M.
Published: November 2019

Manipulating the equilibrium between a ketone and an enol by exposure to light opens up ample opportunities in material chemistry and photopharmacology since it allows one to reversibly control the content of the enol tautomer, which acts as a hydrogen atom donor, with high spatio-temporal and energy resolution. Although tautomerization of β-ketoesters or their analogs was studied in numerous papers, their light-induced reversible tautomerization to give thermally stable enols (photoenolization) is an unexplored area. To shed light on this “blind spot”, we report an unprecedented property of diarylethene 2A assembled from fragments of photoactive dithienylethene and a β-ketoester as part of the cyclohexenone bridge. In a pristine state, the tautomeric equilibrium of 2 is almost completely shifted towards the ketone. Photocyclization of the hexatriene system results in a new equilibrium system containing a significant fraction of the enol tautomer, both in polar and non-polar solvents. Due to the considerable spectral separation (35 nm), the keto-enol tautomerization process could be observed visually. The tendency of 2A to undergo light-induced enolization was proved by isolating a related byproduct of photochemical 1,2-dyotropic rearrangement stabilized in the enolic form. Our results provide a novel tool for controlling the keto-enol tautomerism that might find use in the development of novel photocontrollable processes.
Zeolite Structure Direction: Identification, Strength and Involvement of Weak CH…O Hydrogen Bonds
Authors: Mineva Tzonka , Dib Eddy , Gaje Arnold , Petitjean Hugo , Bantignies Jean-Louis , Alonso Bruno
Published: November 2019

Abstract: We demonstrate herein that weak CH…O hydrogen bonds (HB) play a significant role in zeolite structure direction using organocations. This type of HB were identified between alkyl groups of the organic structure directing agent (OSDA) and the silica framework in as synthesized silicalite-1 of complex topology (MFI) using a combination of experimental and theoretical data obtained at low and room temperatures. The 28 weak CH…O HB, evidenced along dynamics simulation at room temperature, represent 30% of the energy of the Coulomb electrostatic interaction between OSDA and the zeolite framework. The strongest and most stable HB found here connects the OSDA to the [415262] cage containing F atoms and should contribute to preserve zeolite topology during crystal growth. An inspection of other as-synthesized zeolites of very different framework topology indicates that the directional CH...O HBs have to be considered when discussing zeolite structure directing phenomena.
Modulated Structure Determination and Ion Transport Mechanism of Oxide-Ion Conductor CeNbO4+δ
Authors: Li Jian , Pan Fengjuan , Geng Shipeng , Lin Cong , Allix Mathieu , Kuang Xiaojun , Lin Jianhua , Sun Junliang
Published: November 2019

CeNbO4+δ, a family of oxygen hyperstoichiometry materials with varying oxygen contents (CeNbO4, CeNbO4.08, CeNbO4.25, CeNbO4.33) and showing mixed electronic and oxide ionic conduction, have been known for four decades. However, the oxide ionic transport mechanism has remained unclear due to the unknown atomic superstructures of CeNbO4.08 and CeNbO4.33. Here, we determinate the complex superstructures of CeNbO4.08 (89 unique atoms), CeNbO4.25 (75 unique atoms) and CeNbO4.33 (19 unique atoms) by using recently developed continuous rotation electron diffraction (cRED) technique from nano single crystals. The Ce cationic size contraction upon oxidation in CeNbO4+δ allows not only excess oxygen incorporation into the CeNbO4 host lattice at the interstitial site within the Ce cation chains (referred to as Oi), but also relaxation of the NbOn polyhedra in CeNbO4.08, CeNbO4.25, CeNbO4.33 being bridged through mixed corner/edge-sharing in 3-dimentional directions. Two kinds of oxide ion migration events are identified in CeNbO4.08 and CeNbO4.25 phases by molecular dynamic simulations, which form long-rang 3-dimensional migration pathway through the interstitial sites Oi via a synergic-cooperation knock-on mechanism involving continuous breaking and reformation of Nb2O9 units. However, the excess oxygen in the CeNbO4.33 phase hardly migrates because of ordered distribution of high-concentration excess oxide ions. The relationship between the structure and oxide ion migration for the whole series of CeNbO4+d compounds elucidated here provides a direction for the performance optimization of these compounds and the development of oxygen hyperstoichiometric materials for wide variety of applications.
Models for Understanding Divergent Reactivity in Lewis Acid-Catalyzed Transformations of Carbonyls and Olefins
Authors: Becker Marc R. , Reid Jolene P. , Rykaczewski Katie , Schindler Corinna
Published: November 2019

Carbonyl-ene, Prins and carbonyl-olefin metathesis reactions represent powerful strategies for carbon-carbon bond formation relying on Lewis acid catalysts. Although common Lewis acids are able to provide efficient activation, the reactions often proceed with low regio-, or chemoselectivity while high selectivity frequently requires the use of well-designed metal-ligand complexes. Here we demonstrate that simple Lewis acids including Me2AlCl, FeCl3, and SnCl4 can show remarkable selectivity in dif-ferentiating between distinct transformations of carbonyl and olefin functional groups resulting in either carbonyl-ene or carbonyl-olefin metathesis products. Specifically, we report the development of predictive multivariate linear regression models that rely on kinetic and thermodynamic information obtained in DFT calculations to gain important insights into the complex potential energy surfaces (PES) of these competing reaction paths. The presented results further our understanding of Lewis acid reactivity and suggest that even simple Lewis acids have the potential to function as highly selective catalysts.
Pt-Pd Nanoalloy for the Unprecedented Activation of Carbon-Fluorine Bond at Low Temperature
Authors: Dhital Raghu Nath , nomura keigo , Sato Yoshinori , Haesuwannakij Setsiri , Ehara Masahiro , Sakurai Hidehiro
Published: November 2019

Carbon-Fluorine (C-F) bonds are considered the most inert organic functionality and their selective transformation under mild conditions remains challenging. Herein, we report a highly active Pt-Pd nanoalloy as a robust catalyst for the transformation of C-F bonds into C-H bonds at low temperature, a reaction that often required harsh conditions. The alloying of Pt with Pd is crucial to activate C-F bond. The reaction profile kinetics revealed that the major source of hydrogen in the defluorinated product is the alcoholic proton of 2-propanol, and the rate-determining step is the reduction of the metal upon transfer of the beta-H from 2-propanol. DFT calculations elucidated that the key step is the selective oxidative addition of the O-H bond of 2-propanol to a Pd center prior to C-F bond activation at a Pt site, which crucially reduces the activation energy of the C-F bond. Therefore, both Pt and Pd work independently but synergistically to promote the overall reaction.
First-Principles Characterization and Comparison of Clean, Hydrated, and Defect α-Al2O3 (110) Surfaces
Authors: abbaspour tamijani ali , Bjorklund Jennifer , Catalano Jeffrey , Mason Sara E.
Published: November 2019

Structural models of the (110) termination of α-Al2O3 are studied using density functional theory (DFT) calculations and thermodynamics modeling to determine the details of the mineral-water interface structure. It has been established for other facets of both alumina and isostructural hematite that surface preparation conditions can influence the stoichiometry and structure observed during in situ experimental characterization studies. To this end, we use theory and modeling to determine the thermodynamically preferred surface structures as a function of the chemical environment, in terms of the oxygen chemical potential, pressure, and temperature. Consistent with studies of other facets of alumina, we find that thermodynamically unfavorable defect structures, upon hydration and hydroxylation, can show greater stability than the hydrated forms of ideal terminations. The model results are compared to experimental characterization of the hydrated (110) surface, with good agreement in terms of layer spacings and calculated surface-free energies. The electronic structure of the exposed surface functional groups is presented and discussed in terms of structure-reactivity concepts used in geochemical surface science.
Microbial Cleavage of C‒F Bonds in Per- and Polyfluoroalkyl Substances via Dehalorespiration
Authors: Yu Yaochun , Zhang Kunyang , Li Zhong , Ren Changxu , Liu Jinyong , Men Yujie
Published: November 2019

Regarding the emerging concerns of the widely occurred and environmentally persistent per- and polyfluoroalkyl substances (PFASs), one intriguing and unsolved scientific question for environmental microbiologists, chemists, and engineers is that whether microbial reductive defluorination of perfluorinated compounds exist in nature. Due to the strong dissociation energy of carbon‒fluorine (C‒F) bonds in PFASs, no convincing evidence for biological cleavage of C‒F bonds from > C2 perfluorinated structures has ever been reported. We for the first time show C‒F bond cleavage via reductive defluorination by an organohalide-respiring microbial community for two PFASs, perfluoro(4-methylpent-2-enoic acid) and 4,5,5,5-tetrafluoro-4-(trifluoromethyl)-2-pentenoic acid. Comprehensive biotransformation pathways are further elucidated. This study brings valuable fundamental knowledge of microbial dehalorespiration, which opens avenues for the future exploration of PFAS environmental fate and bioremediation strategies.
Determination of Protein Structural Ensembles by Hybrid-Resolution SAXS Restrained Molecular Dynamics.
Authors: Paissoni Cristina , Jussupow Alexander , Camilloni Carlo
Published: November 2019

SAXS experiments provide low-resolution but valuable information about the dynamics of biomolecular systems, which could be ideally integrated into MD simulations to accurately determine conformational ensembles of flexible proteins. The applicability of this strategy is hampered by the high computational cost required to calculate scattering intensities from three-dimensional structures. We previously presented a hybrid resolution method that makes atomistic SAXS-restrained MD simulation feasible by adopting a coarse-grained approach to efficiently back-calculate scattering intensities; here, we extend this technique, applying it in the framework of metainference with the aim to investigate the dynamical behavior of flexible biomolecules. The efficacy of the method is assessed on the K63-diubiquitin, showing that the inclusion of SAXS-restraints is effective in generating a reliable conformational ensemble, improving the agreement with independent experimental data.
NILAI TBA, FFA, KADAR AIR DAN SIFAT SENSORI KERIPIK KENTANG BERDASARKAN JENIS KEMASAN DAN LAMA PENYIMPANAN
Authors: Fajriyani Azqia , Hersoelistyorini Wikanastri , Nurhidajah Nurhidajah
Published: November 2019

Potato (Solanum tuberosum L.) is one type of tubers are widely consumed by the community because it tastes good and contains high carbohydrates. Potato damage easily occurs because the water content in potatoes is high enough that is 80 percent. Based on that, it is necessary to do the processing to extend the life of the potato store. This study aims to determine the effect of packaging type and storage time to the value of TBA, FFA, Water Content and Sensory Character of Potato Chips. This study used a factorial completely randomized design consisting of 2 factors: packaging type (PP, PE, and aluminum foil) with each thickness of 0.5 mm and storage time (0 days, 7 days, 14 days, 21 days and 28 day) in room temperature. The result of statistical test showed that the type of packaging and storage time had an effect on FFA value, water content and sensory character of potato chips while the value of TBA had no significant effect. Level of potato chip TBA at end of shelf in packing PP 2,412 mg malonaldehid / kg sample, PE 3,365 mg malonaldehid / kg and aluminum foil 2,787 mg malonaldehid / kg sample. FFA value at end of shelf life on packing PP1,173% ALB sample, PE 1,548% ALB sample, and Alumunium foil 1.173% ALB sample. Water content at end of shelf life on PP 7.040%, PE 3,933%, and Alumunium foil 3,003%. The result of statistical test shows that there is influence of packaging type and storage time to FFA value, water content and sensory character of potato chips.
PENANGANAN KERAK PADA HANDLING EQUIPMENT MACHINE
Authors: Novianto Rizki
Published: November 2019

Pengerakan Ferro karbonat tidak hanya fenomena kristalisasi yang terbentuk dalam proses alami (biomineralization), tetapi merupakan masalah yang sering ditemui dalam berbagai alat berat seperti bulldozer (Alice et al., 2011). Hal ini disebabkan karena terdapatnya unsur-unsur pembentuk kerak seperti besi dan karbonat dalam jumlah yang melebihi kelarutannya pada peralatan berat. Kerak biasanya mengendap dan tumbuh pada peralatan industri seperti pada pipa pipa hidrolik alat berat. Kerak merupakan suatu deposit dari senyawa-senyawa anorganik yang terendapkan dan membentuk timbunan kristal pada permukaan suatu subtansi. Kerak merupakan suatu deposit dari senyawa-senyawa anorganik yang terendapkan dan membentuk timbunan kristal pada permukaan suatu subtansi.  Hal ini disebabkan karena terdapatnya unsur-unsur pembentuk kerak seperti alkalin, magnesium, kalsium, klorid, sulfat dalam jumlah yang melebihi kelarutannya pada keadaan kesetimbangan. Kerak biasanya mengendap dan tumbuh pada peralatan industri seperti cooling tower, heat exchangers, pipe, casing manifold, tank dan peralatan industri lainnya
PENGAMATAN TERJADINYA KERAK CuCO3 PADA KETEL UAP
Authors: Novianto Adi
Published: November 2019

Kerak tembaga karbonat (CuCO3) yang mengendap pada dinding pipa diselidiki dalam penelitian ini. Kerak tembaga karbonat adalah kerak yang sering terbentuk pada pipa boiler. Dalam eksperimental, larutan pembentuk kerak disiapkan dengan mencampurkan larutan equimolar CuCl2 dan Na2CO3. Tujuan dari penelitian ini adalah untuk membandingkan hasil penelitian tentang pembentukan kerak CuCO3 pada pipa boiler kerak CuCO3 dan pada pipa simulasi dengan suhu 300-4000C. Kerak yang terbentuk kemudian dievaluasi menggunakan analisis karakteristik kerak dan SEM/EDX. Hasil penelitian menunjukkan bahwa kerak memiliki pelat seperti morfologi dan kerak fase kristal yang ditemukan sebagian besar malasite. Berdasarkan hasil ini, kerak CuCO3 di Boiler memiliki kondisi panas yang sangat tinggi dan waktu panas yang lama membuat kerak CuCO3 berwarna hitam. Warna dan tekstur kerak CuCO3 pada pipa menunjukkan warna yang lebih cerah. Kerak yang terbentuk kemudian dievaluasi menggunakan analisis SEM / EDX. Perbandingan analisis antara hasil analisis kerak CuCO3 pada pipa boiler dan pipa simulator menunjukkan hasil yang berbeda. Hasil analisis SEM menunjukkan bahwa kristal yang dilakukan melalui eksperimen diambil dari boiler dan pipa. Perbedaan morfologi dan komposisi antara sampel kedua adalah karena boiler lebih panas daripada di pipa sehingga morfologi kristal CuCO3 dalam boiler lebih rapat dibandingkan di pipa.
EVALUASI SIFAT MEKANIK HIGH DENSITY POLYETHYLENE YANG DIISI SERAT BATANG PISANG DAN PARTIKEL ZEOLIT ALAM
Authors: Nurcahyanto Hardiman
Published: November 2019

Pohon pisang yang merupakan limbah, dimanfaatkan pelepahnya untukdiambil seratnya guna pembuatan komposit. Pada penelitian ini dilakukanuntuk mengetahui potensi sifat mekanik serat batang pisang yangdikombinasikan dengan serbuk mineral Zeolit, dan HDPE (Hight densitypolyethylene) sebagai matrik komposit ini. Untuk mengetahui sifat mekanikpada komposit dilakukan uji tarik ASTM D 638-02 dan DENT. Sebelumdijadikan komposit, serat dilakukan treatment menggunakan larutan NaOH5% selama 2 jam dan dikeringkan pada suhu kamar selama 3-4 hari. Metodepembuatan komposit yaitu menggunakan injeksi molding (injectionmoulding) yang sebelumya dilakukan penyerbukan semua bahan agartercampur sempurna dengan variasi komposisi serat zeolit berturut-turut2%:3%, 3%:2%, 4%:1% dan ligamen dengan variasi panjang 6 mm, 8 mm,dan 10 mm untuk spesimen uji. Hasil yang didapatkan komposit pengujiankomposit dalam penelitian ini berupa uji kekuatan tarik menurut standartASTM D 638-02 dan DENT. Hasil pengujian tarik dengan standart ASTM D638-02 didapat nilai tertinggi maximum force, elongation, modulus young, dantensile strength terdapat pada HDPE murni dengan nilai maximum force678,90 Newton, elongation 16%, modulus young 514,50 N/mm2 dan tensile strength 22,63 N/mm2. Ketangguhan fracture We (essensial kerja) komposit terdapat pada spesimen komposit serat 4% zeolit 1% dengan nilai 203,27kJ/m². Dapat disimpulkan komposit serat 4% zeolit 1%  memiliki hubunganlinier we (essensial kerja) yang baik dibandingkan pada komposit lainnya.