bluuebunny/crossref_metadata_2025 huggingface dataset:
MiNNLO$$_{\text {PS}}$$: optimizing $$2\rightarrow 1$$ hadronic processes
Authors: Monni Pier Francesco , Re Emanuele , Wiesemann Marius
Published: November 2020

We consider the MiNNLO$$_\mathrm{PS}$$

PS

method to consistently combine next-to-next-to-leading order (NNLO) QCD calculations with parton-shower simulations. We identify the main sources of differences between MiNNLO$$_\mathrm{PS}$$

PS

and fixed-order NNLO predictions for inclusive observables due to corrections beyond NNLO accuracy and present simple prescriptions to either reduce or remove them. Refined predictions are presented for Higgs, charged- and neutral-current Drell Yan production. The agreement with fixed-order NNLO calculations is considerably improved for inclusive observables and scale uncertainties are reduced. The codes are released within the POWHEG-BOX.
THE UNIQUE EXISTENCE OF SOLUTION IN THE q-INTEGRABLE SPACE FOR THE NONLINEAR q-FRACTIONAL DIFFERENTIAL EQUATIONS
Authors: ZHANG TIE , WANG YUZHONG
Published: November 2020

In this paper, we study the solution theory of the nonlinear [Formula: see text]-fractional differential equation of Caputo type [Formula: see text] with given initial values [Formula: see text] where [Formula: see text] is the order, [Formula: see text] and [Formula: see text] is the scale index. For [Formula: see text], by assuming that function [Formula: see text] is bounded and satisfies the Lipschitz condition on variable [Formula: see text], we prove that this problem admits a unique solution in the [Formula: see text]-integrable function space [Formula: see text] and this solution is absolutely stable in the [Formula: see text]-norm. This unique existence condition allows that [Formula: see text] is singular at [Formula: see text] and discontinuous for [Formula: see text]. Finally, a successive approximation method is presented to find out the analytic approximation solution of this problem.
STABILITY ANALYSIS OF NONLINEAR UNCERTAIN FRACTIONAL DIFFERENTIAL EQUATIONS WITH CAPUTO DERIVATIVE
Authors: LU ZIQIANG , ZHU YUANGUO , LU QINYUN
Published: November 2020

Uncertain fractional differential equation driven by Liu process plays a significant role in depicting the memory effects of uncertain dynamical systems. This paper mainly investigates the stability problems for the Caputo type of uncertain fractional differential equations with the order [Formula: see text]. The concept of stability in measure of solutions to uncertain fractional differential equation is proposed based on uncertainty theory. Several sufficient conditions for ensuring the stability of the solutions are derived, respectively, in which the systems are divided into two cases with order [Formula: see text] and [Formula: see text]. Some illustrative examples are performed to display the effectiveness of the proposed results.
OPIAL-TYPE INEQUALITY ABOUT CONFORMABLE FRACTIONAL INTEGRALS AND THE APPLICATION
Authors: QI YONGFANG , LI GUOPING , WANG XIAOYUAN
Published: November 2020

In this paper, we define partial conformable fractional derivative (PCFD) which is based on the fractional derivative definition proposed by Abdeljawad. At the same time, we present some simple properties about the definition, the properties are useful for us when we carry out further research. In addition, taking advantage of Hölder’s inequality, we establish Opial-type inequalities for the partial conformable fractional (PCF) integral. As an application, the uniqueness of the partial system with initial value is proved.
Asymptotics for the fourth-order nonlinear Schrödinger equation in 2D
Authors: Naumkin Pavel I.
Published: November 2020

Our aim is to study the large time asymptotics of solutions to the fourth-order nonlinear Schrödinger equation in two space dimensions [Formula: see text] where [Formula: see text] We show that the nonlinearity has a dissipative character, so the solutions obtain more rapid time decay rate comparing with the corresponding linear case, if we assume the nonzero total mass condition [Formula: see text] We continue to develop the factorization techniques. The crucial points of our approach presented here are the [Formula: see text] — estimates of the pseudodifferential operators and the application of the Kato–Ponce commutator estimates.
Existence of two-solitary waves with logarithmic distance for the nonlinear Klein–Gordon equation
Authors: Aryan Shrey
Published: November 2020

We consider the focusing nonlinear Klein–Gordon (NLKG) equation [Formula: see text] for [Formula: see text] and [Formula: see text] subcritical for the [Formula: see text] norm. In this paper, we show the existence of a solution [Formula: see text] of the equation such that [Formula: see text] where [Formula: see text] are two solitary waves of the equation with translations [Formula: see text] satisfying [Formula: see text] This behavior is due to the strong interactions between solitary waves which is in contrast with the previous work [R. Côte and Y. Martel, Multi-travelling waves for the nonlinear Klein–Gordon equation, Trans. Amer. Math. Soc. 370(10) (2018) 7461–7487] on multi-solitary waves of the (NLKG), devoted to the case of solitary waves with different speeds. This work is motivated by previous similar existence results for the nonlinear Schrödinger and generalized Korteweg–de Vries equations.
Skew braces of size p2q II: Non-abelian type
Authors: Acri E. , Bonatto M.
Published: November 2020

In this paper we enumerate the skew braces of non-abelian type of size [Formula: see text] for [Formula: see text] primes with [Formula: see text] by the classification of regular subgroups of the holomorph of the non-abelian groups of the same order. Since Crespo dealt with the case [Formula: see text], this paper completes the enumeration of skew braces of size [Formula: see text] started in a previous work by the authors. In some cases, we provide also a structural description of the skew braces. As an application, we prove a conjecture posed by Bardakov et al.
MODELING AND PERFORMANCE ANALYSIS FOR THE URETHRAL VALVE USED TO MANAGE SEVERE URINARY INCONTINENCE
Authors: LI YAPENG , LI XIAO , ZHANG RAN , CAO RUI , GUAN TING
Published: November 2020

This paper presents a new urethral valve to deal with severe urinary incontinence (UI) caused by sphincter injury or dysneuria. This valve consists of a wireless power transfer system and a valve body structure driven by SMA (shape memory alloy) spring. The mechanical model of SMA spring and coupling model of wireless energy transfer are derived. Special attention is also given to the biological effects of electromagnetic filed as the proposed device is powered by wireless power transfer system. This valve is validated by simulation experiment and the models are used to investigate the influence of SMA spring parameters, control parameters and coil parameters on the driving characteristics of the proposed urethral valve.
Facile Fabrication of C-Modified Bi2WO6 Photocatalysts with Enhanced Tetracycline Degradation Under Visible Light
Authors: Yu Yang , Huang Yanju , Li Xiumei
Published: November 2020

In order to realize the rational utilization of wastewater treatment, an efficient and conductive 3D hierarchical flowers globose nanostructure of Bi2WO6/C is explored from the withered peach blossom for removing the contaminants. As a consequence, Bi2WO6/C shows a better degradation efficiency for tetracycline (TC) than Bi2WO6 (49%) under visible light, when the mass ratio of Bi2WO6 to C is 6:1. Additionally, photoelectrochemical measurements proved that the separation efficiency of electron–hole pairs of Bi2WO6 is enhanced by the introduction of biomass carbon, due to its good electron transmission ability. Moreover, the mechanism exploration experiment showed that [Formula: see text] was the main activity species. Meanwhile, the photocatalytic electron transfer mechanism was also investigated. The favorable photocatalytic performances make the waste biomass carbon act as a new resource for being applied to antibiotic wastewater treatment.
Assessing the impact of transmissibility on a cluster-based COVID-19 model in India
Authors: Tanvi  , Sajid Mohammad , Aggarwal Rajiv , Rajput Ashutosh
Published: November 2020

In this paper, we have proposed a nonlinear mathematical model of different classes of individuals for coronavirus (COVID-19). The model incorporates the effect of transmission and treatment on the occurrence of new infections. For the model, the basic reproduction number [Formula: see text] has been computed. Corresponding to the threshold quantity [Formula: see text], the stability of endemic and disease-free equilibrium (DFE) points are determined. For [Formula: see text], if the endemic equilibrium point exists, then it is locally asymptotically stable, whereas the DFE point is globally asymptotically stable for [Formula: see text] which implies the eradication of the disease. The effects of various parameters on the spread of COVID-19 are discussed in the segment of sensitivity analysis. The model is numerically simulated to understand the effect of reproduction number on the transmission dynamics of the disease COVID-19. From the numerical simulations, it is concluded that if the reproduction number for the coronavirus disease is reduced below unity by decreasing the transmission rate and detecting more number of infectives, then the epidemic can be eradicated from the population.
Rotary Compressor Performance at Low Ambient Temperatures
Authors: Lowrey S. , Reboux G.
Published: November 2020

Small rotary compressors are used in domestic heat pump appliances, for example, in domestic dehumidifiers and heat pump clothes dryers. Compressor performance curves provided by the manufacturer can be based on testing at relatively high ambient temperatures, in some cases as high as 35∘C. This can be much higher compared with the ambient temperature in which the compressor operates when, for example, it is installed in a domestic dehumidifier which can operate in ambient temperatures as low as 10∘C.

We have developed a compressor calorimeter to test a small R134a rotary compressor extracted from a commercial domestic dehumidifier and use this to measure compressor performance parameters including the isentropic and volumetric efficiencies and the compressor heat loss fraction. The performance testing has been carried out at ambient temperatures 10∘C, 15∘C, 20∘C and 25∘C for a fixed relative humidity of 70% to compare how the compressor performance varies with the ambient temperature, and to determine how well the compressor performs outside of the performance envelope provided by the manufacturer. The results show that isentropic and volumetric efficiency of these small compressors is relatively insensitive to variation in ambient temperature, even outside of the performance envelope provided by the manufacturer. However, the compressor heat loss fraction can, on average, double from 15% to 30%, between operation at ambient 25∘C and ambient 10∘C.

The data obtained in this work is used to construct compressor sub-models for certain ambient temperatures. We show how these sub-models can be used to improve a domestic dehumidifier model for operation at low ambient conditions within the evaporator frosting regime and good agreement is obtained between experimental and simulated data. The authors are not aware of a domestic dehumidifier model designed to work at ambient temperatures within the frosting regime.
The Time I Stole $10,000 from Bell Labs
Authors: Limoncelli Thomas A.
Published: November 2020

If IT workers fear they will be punished for outages, they will adopt behavior that leads to even larger outages. Instead, we should celebrate our outages: Document them blamelessly, discuss what we've learned from them openly, and spread that knowledge generously. An outage is not an expense. It is an investment in the people who have learned from it. We can maximize that investment through management practices that maximize learning for those involved and by spreading that knowledge across the organization. Managed correctly, every outage makes the organization smarter. In short, the goal should be to create a learning culture?one that seeks to make only new mistakes.
Kabin Fever
Authors: Neville-Neil George V.
Published: November 2020

Let me invite you to my next Zoom meeting on how to host Zoom meetings! As a devotee of mobile computing and remote work from my earliest days at university, I have, over time, developed a number of useful habits for maintaining a good and productive working rhythm, and I've found that many of these apply well to those of you who are newly working from home.
Successful Technique for Closure of Macular Hole Retinal Detachment Using Autologous Retinal Transplant
Authors: Ramirez-Estudillo Juan Abel , Rios-Nequis Geovanni , Jimenez-Rodríguez Martin , Valdez-Flores Hugo , Ramirez-Galicia Ximena
Published: November 2020

Macular hole retinal detachment (MHRD) for the most part develops in highly myopic eyes. Several surgical methods have been introduced to treat MHRD. We describe our experience with the autologous retinal transplant in patient with MHRD. A 49-year-old female presented with a 2-week history of a sudden decrease in the central vision in the right eye (RE). A 3-port, 25-gauge pars plana vitrectomy was performed with the ILM dye staining and peeling. Endodiathermy was applied around a 1.5-disc diameter neurosensory donor site in the supertemporal retina. The graft was cut with standard 25-gauge curved scissors. Perfluoro-n-octane (PFO) was instilled. The free graft was gently handled until its packing into the macular hole. Two months following the initial PPV, the macular hole was closed, and vision improved from 0.05 to 0.25 logMAR.
Community Detection Based on DeepWalk Model in Large-Scale Networks
Authors: Chen Yunfang , Wang Li , Qi Dehao , Ma Tinghuai , Zhang Wei
Published: November 2020

The large-scale and complex structure of real networks brings enormous challenges to traditional community detection methods. In order to detect community structure in large-scale networks more accurately and efficiently, we propose a community detection algorithm based on the network embedding representation method. Firstly, in order to solve the scarce problem of network data, this paper uses the DeepWalk model to embed a high-dimensional network into low-dimensional space with topology information. Then, low-dimensional data are processed, with each node treated as a sample and each dimension of the node as a feature. Finally, samples are fed into a Gaussian mixture model (GMM), and in order to automatically learn the number of communities, variational inference is introduced into GMM. Experimental results on the DBLP dataset show that the model method of this paper can more effectively discover the communities in large-scale networks. By further analyzing the excavated community structure, the organizational characteristics within the community are better revealed.
An Empirical Study on Customer Segmentation by Purchase Behaviors Using a RFM Model and K-Means Algorithm
Authors: Wu Jun , Shi Li , Lin Wen-Pin , Tsai Sang-Bing , Li Yuanyuan , Yang Liping , Xu Guangshu
Published: November 2020

In this paper, we base our research by dealing with a real-world problem in an enterprise. A RFM (recency, frequency, and monetary) model and K-means clustering algorithm are utilized to conduct customer segmentation and value analysis by using online sales data. Customers are classified into four groups based on their purchase behaviors. On this basis, different CRM (customer relationship management) strategies are brought forward to gain a high level of customer satisfaction. The effectiveness of our method proposed in this paper is supported by improvement results of some key performance indices such as the growth of active customers, total purchase volume, and the total consumption amount.
Log Odds of Positive Lymph Node- (LODDS-) Based Competing-Risk Nomogram for Predicting Prognosis of Resected Rectal Cancer: A Development and Validation Study
Authors: Zheng Rui-zhe , Xie Jiang , Zhang Shui-qiang , Li Wen , Dong Bo , Cong Yin-wei , Wang Zhi-qiang
Published: November 2020

Background and Aims. Cancer-specific survival (CSS) of rectal cancer (RC) is associated with several factors. We aimed to build an efficient competing-risk nomogram based on log odds of positive lymph nodes (LODDS) to predict RC survival. Methods. Medical records of 8754 patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database, of 4895 patients from SEER during 2011–2014 and of 478 patients from an Eastern center as a development cohort, validation cohort, and test cohort, respectively. Univariate and multivariate competing-risk analyses were performed to build competing-risk nomogram for predicting the CSS of RC patients. Prediction efficacy was evaluated and compared with reference to the 8th TNM classification using the factor areas under the receiver operating characteristic curve (AUC) and Brier score. Results. The competing-risk nomogram was based on 6 variables: size, M stage, LODDS, T stage, grade, and age. The competing-risk nomogram showed a higher AUC value in predicting the 5-year death rate due to RC than the 8th TNM stage in the development cohort (0.81 vs. 0.76), validation cohort (0.85 vs. 0.82), and test cohort (0.71 vs. 0.66). The competing-risk nomogram also showed a higher Brier score in predicting the 5-year death rate due to RC than the 8th TNM stage in the development cohort (0.120 vs. 0.127), validation cohort (0.123 vs. 0.128), and test cohort (0.202 vs. 0.226). Conclusion. We developed and validated a competing-risk nomogram for RC death, which could provide the probability of survival averting competing risk to facilitate clinical decision-making.
Outcomes of Flank-Free Modified Supine Percutaneous Nephrolithotomy Based on BMI
Authors: Desoky Esam , Abd Elwahab Khaled M. , El-Babouly Islam M. , Seleem Mohammed M.
Published: November 2020

Objective: To evaluate the impact of body mass index (BMI) on the outcomes of percutaneous nephrolithotomy (PCNL) in the flank-free modified supine position. Patients and Methods: A prospective study was carried out in the urology department during the period from May 2015 to October 2019 on 464 patients admitted for PCNL. The patients were divided into 4 matched groups according to their BMI: group A, normal weight with 18.5 ≤ BMI <25 kg/m2; group B, overweight with 25 ≤ BMI <30 kg/m2; group C, obese with 30 ≤ BMI <40 kg/m2; and group D, morbid obesity with BMI ≥40 kg/m2. All operative data as well as postoperative outcomes are recorded and compared to each other. Results: The 4 studied groups were matched regarding age. The comorbidities were slightly higher in groups C and D. The operative time and fluoroscopy time were slightly high in obese and morbid obese groups but with no significant difference. The rate of complications either major or minor was comparable in all groups. No significant difference was seen among all groups regarding hemoglobin loss, stone-free rate, hospital stay, and need for auxiliary procedures. Conclusions: The outcome of PCNL in flank-free modified supine position is not affected by changes in BMI. The procedure can be performed in obese and morbid obese patients safely with results similar to and comparable to nonobese patients.
A Failed Cardiac Surgery Program in an Underserved Minority Population County Reimagined: The Power of Partnership
Authors: Brown James M. , Hajjar‐Nejad M. J. , Dominique Guerda , Gillespie Malinda , Siddiqi Imran , Romine Heather , Odonkor Patrick , Dawood Murtaza , Gammie James S.
Published: November 2020

Background

Prince George's County Maryland, historically a medically underserved region, has a population of 909 327 and a high incidence of cardiometabolic syndrome and hypertension. Application of level I evidence practices in such areas requires the availability of highly advanced cardiovascular interventions. Donabedian principles of quality of care were applied to a failing cardiac surgery program. We hypothesized that a multidisciplinary application of this model supported by partnership with a university hospital system could result in improved quality care outcomes.

Methods and Results

A 6‐month assessment and planning process commenced in July 2014. Preoperative, intraoperative, and postoperative protocols were developed before program restart. Staff education and training was conducted via team simulation and rehearsal sessions. A total of 425 patients underwent cardiac surgical procedures. Quality tracking of key performance measures was conducted, and 323 isolated coronary artery bypass grafting procedures were performed from July 2014 to December 2019. Key risk factors in our patient demographic were higher than the Society of Thoracic Surgeons national mean. Risk‐adjusted outcome data yielded a mortality rate of 0.3% versus 2.2% nationally. The overall major complication rate was lower than expected at 7.1% compared with 11.5% nationally. Readmission rate was less than the Society of Thoracic Surgeons mean for isolated coronary artery bypass grafting (4.0% versus 10.1%,
P
<0.0001). Significant differences in 6 key performance outcomes were noted, leading to a 3‐star Society of Thoracic Surgeons designation in 7 of 8 tracking periods.

Conclusions

Excellent outcomes in cardiac surgery are attainable following program renovation in an underserved region in the setting of low volume. The principles and processes applied have potential broad application for any quality improvement effort.
Hippocrates and Galen in Turfan
Authors: Lin Lijuan
Published: November 2020

This article presents a full edition, with translation and detailed commentary, of SyrHT 1 and SyrHT 388, the only two Syriac medical fragments found in Turfan. Based on a re-examination of the original text, this article shows that the Turfan fragments have parallels in Galen’s De compositione medicamentorum secundum locos and contain elements of Hippocratic recipes as well. This adds further evidence that Syriac Christians had brought Hellenistic medical lore to Turfan at an early date.
The Verb yhb in Aramaic
Authors: Fox Samuel Ethan , Fassberg Steven E.
Published: November 2020

On the whole, the verb yhb ‘give’ occurs in suppletion with ntn in Pre-Modern Aramaic: the former is found in the perfect, participle, and imperative, and the latter in the imperfect and infinitive. There are exceptions in some corpora. Only yhb, however, has survived into Neo-Aramaic, where it is attested in all varieties of the language. This article traces the use of both roots in the history of Aramaic and focuses on the different Neo-Aramaic reflexes of yhb. An explanation is offered for the development of the various Neo-Aramaic forms.
The Zuqnin Chronicle as Evidence of Vernacular Aramaic in Eighth-Century Northern Mesopotamia
Authors: Furman Julia
Published: November 2020

This article examines a Syriac historiographical writing of the late eighth century—the so-called Zuqnin Chronicle, or the Chronicle of Pseudo-Dionysius of Tell Maḥre—and certain lexical features that are found at the end of the work. It is argued that these lexical items were drawn into the chronicle from a colloquial Aramaic language spoken in the vicinity of Amid, and that this colloquial variant is linked with the Neo-Aramaic language Turoyo. In addition, the article offers a methodology for identifying colloquial Aramaic words in the corpus of Classical Syriac literature.
‘Whoever Is Hungry, Come and Eat’
Authors: Gross Simcha
Published: November 2020

The provenance of the opening Aramaic portion of the Passover Haggadah has confounded practitioners and scholars for centuries. Little evidence has come to light to explain the origins of this passage or the fluctuations in its attending practices over time. This article argues that additional evidence, found in some neglected Talmudic manuscripts and in incantation bowls, reveals that the core recitational and practical elements of this passage were originally unrelated to Passover or Jewish ritual. Instead, they were part of a recognised social script in late antique Jewish Babylonia that was integrated into the Passover Haggadah. With changes in Babylonian Jewish society, and with the transmission of this section and its associated practices to Jewish communities outside of Babylonia, the original social and cultural context of this sentence was forgotten. Untethered from the setting in which it was culturally legible, it developed through encounters with new actors in different contexts.
Populism in Estonia and Slovakia: Performances, Transgressions, and Communicative Styles
Authors: Kazharski Aliaksei , Makarychev Andrey
Published: November 2020

The paper relies on empirical evidence from Estonia and Slovakia to develop an understanding of populism as a performative and transgressive political style. We argue that populism cannot be defined in ideological terms nor can it be attached to particular political subjects. Instead, it is a political style that can be adopted and mimicked by various subjects from extreme right to social liberal. The performativity of populism presupposes forms of transgression that disrupt the normalcy of political routine. Populist performances thus seek and construct an authenticity by taking politics outside of its conventional institutional frameworks. We examine the cases of EKRE in Estonia and ĽSNS and OĽaNO in Slovakia.
New Adsorption Models for Entirely Describing the Adsorption Isotherm and Heat of Methane in Heterogeneous Nanopore Structures of Coal
Authors: Li Hai-Jian , Kang Jian-Hong , Pan Zhe-Jun , Zhou Fu-Bao , Deng Jin-Chang , Zhu Shuang-Jiang
Published: November 2020

To understand the adsorption mechanism of methane in heterogeneous nanopore structures of coal, integral adsorption models based on linear, exponential, hyperbolic and quadratic energy distribution functions are established. The adsorption energy domain of the new models is assumed
to be a finite interval. These new adsorption models can describe both the adsorption isotherm and the adsorption heat. A volumetric method of adsorption with a microcalorimetry system is used to measure the adsorption isotherms and integral heat, and then the parameters of the new models
are obtained by fitting the experimental data. Since the adsorption heat can be different for different adsorption models, it is necessary to fit the adsorption isotherms and heat simultaneously. The fitting results of the adsorption isotherms and heat show that the new models are able to
describe the experimental data better than the Langmuir model. By comparing the fitting results and the effective range of adsorption energy of the different adsorption models, it is shown that the exponential energy distribution function is the most reasonable model for methane adsorption
in coals, which can be used to evaluate the energetic heterogeneity of nanopores in coal samples. The decreasing exponential energy distributions of three coal samples indicate that a larger adsorption energy corresponds to fewer adsorption sites in the coal samples. The proportion of high
adsorption energy is related to the micro-nanopore volume in the coal samples.
Fourier Transform Infrared Spectroscopy Evidence of the Nanoscale Structural Jump in Medium-Rank Tectonic Coal
Authors: Zhang Xiaobing , Jia Tianrang , Zhang Hang , Ju Yiwen , Zhang Yugui
Published: November 2020

Coal is a pressure-sensitive organic rock. The effect of tectonism on the structural evolution of medium-rank coal has been confirmed by the change in the crystal state of tectonic coal, but the organic molecular level response has not been reported. In this paper, three sets of medium-rank
tectonic coals and symbiotic nontectonic coals were selected. The distributions of their functional groups and their molecular structure evolution were assessed using Fourier Transform Infrared Spectroscopy (FTIR), and their structural parameters were determined from the curve-fitting analysis.
The nanoscale structural jump characteristics and mechanisms of medium-rank tectonic coal were revealed. Compared with symbiotic nontectonic coal, tectonism accelerated the exfoliation of side chains (groups) in the macromolecular structure, enlarged the aromatic system, and removed the unstable
groups such as associative hydrogen bonds at first, which indicated that the molecular structure of tectonic coal was affected by nanoscale deformation, showing obvious advanced evolution characteristics. For the fat coal, the removal of side chains (groups) during the formation of tectonic
coal makes the aromatic ring condensation obvious. For the coking coal, the formation of tectonic coal is dominated by cycloaliphatic dehydrogenation and aromatization, accompanied by the condensation of the aromatic rings. The tectonic coal formed from lean coal shows obvious aromatization
characteristics. The molecular depolymerization and chemical tailoring caused by tectonism promotes the removal of hydrophobic side chains (groups) and activates some polar structure sites in coal. It is considered that the nanoscale structural jump of medium-rank tectonic coal is the result
of the competition between the aromatic system and aliphatic structures.
Multi-Angle Investigation of the Fractal Characteristics of Nanoscale Pores in the Lower Cambrian Niutitang Shale and Their Implications for CH4 Adsorption
Authors: Wang Yang , Wu Caifang , Qin Yong , Liu Shimin , Zhang Rui
Published: November 2020

Shale gas has received widespread interest due to its successful commercial development in China. Pore structures in shale can directly control its gas storage and migration properties. In this study, field emission scanning electron microscopy (FE-SEM), low-pressure N2/CO2
adsorption and highpressure methane adsorption were used to investigate the nanoscale pore structures of the Lower Cambrian Niutitang Formation in the southeastern Upper Yangtze platform. The fractal parameters of the pore structures were also calculated using the Frenkel–Halsey–Hill
(FHH) model. The relationships between the fractal dimensions and TOC content, mineral composition and pore structure parameters were also discussed. The results show that organic matter and clay minerals are primary factors affecting the nanoscale pore development. Slit-shaped pores and ink-bottle-shaped
pores are the predominant pore types in the Niutitang shale. The Brunauer-Emmett-Teller (BET) surface areas vary from 4.91 m2/g to 34.33 m2/g, and the pore volumes range from 0.689 m3/100 g to 2.964 m3/100 g. Two fractal dimensions (D1
and D2) of the Niutitang shale were obtained using the FHH model, with D1 ranging from 2.605 to 2.684, and D2 ranging from 2.681 to 2.865. D1 adequately characterizes the surface roughness of the pore structures, while
D2 represents the complexity of the pore types. Inter-particle (InterP) pores commonly have greater shape complexities than OM pores and intra-particle (IntraP) pores, based on analyses using Image-Pro Plus software. In addition, the TOC content and clay minerals have great
effects on the fractal dimension D1. Meanwhile, the fractal dimension D1 increases with increasing BET surface area, but there is no definite relationship between the fractal dimensions and pore volumes. Both the fractal dimensions D1 and
D2 are negatively correlated with pore sizes. Further investigation indicates that the fractal dimension D1 exhibits a strong positive relationship with the methane adsorption capacity indicating that Niutitang shales with greater values of the fractal dimension
D1 have higher methane adsorption capacities.
Macromolecular Structural Responses of Coking Coal to Stress–Strain Environments Based on High-Resolution Transmission Electron Microscopy
Authors: Guo Liang , Qu Zhenghui , Xue Zhiwen , Li Hao , Zhang Bicheng , Zhang Chuang
Published: November 2020

In China, most coal seams have experienced multiple phases of tectonics, which increase the complexity of the coal porosity. The responses of macromolecular structures to stress–strain environments are the key to understanding the complexity of coal porosity caused by tectonism.
This study investigated the macromolecular structural response of coking coal to different stress–strain environments. The calculation and analysis of high-resolution transmission electron microscopy (HRTEM) test results for six coking coals with different deformation types and degrees
were performed. The results showed that the macromolecular structure of coking coal has different responses to stress– strain environments. The lattice fringe length, curvature, and d002 parameters are not prominently governed by certain principles increasing shear
and toughness. Furthermore, the lattice fringe tends to be consistent with the deformation. However, the lattice fringe during ductile deformation in the main direction is arranged nearly parallel on the plane. In shear deformation, the lattice fringes are arranged parallel in the principal
direction. This phenomenon is caused by the directional screening of the macromolecular structure of coking coal by stress. Under the action of tectonic stress, the structure hindering tectonic stress is destroyed, and the structure grows in other directions gradually under the promotion of
tectonic stress. As a result, the direction of the whole lattice fringe gradually converges under stress screening after tectonic stress is applied. Therefore, the direction tends to be consistent with the strengthening of the deformation. The response of the other parameters is slow, showing
the coexistence of the old and new orders of direction. The directivity of the macromolecular structure of coal is an important index for reflecting the types and degrees of tectonic deformation.
Pore Size Distribution and Fractal Characteristics of the Nanopore Structure in Organic-Rich Shales Using the Neimark-Kiselev Fractal Approach
Authors: Wei Mingming , Zhang Li , Xiong Yongqiang , Peng Ping’an , Ju Yiwen
Published: November 2020

Shale gas has been playing an increasingly important role in meeting global energy demands. The heterogeneity of the pore structure in organic-rich shales greatly affects the adsorption, desorption, diffusion and flow of gas. The pore size distribution (PSD) is a key parameter of the
heterogeneity of the shale pore structure. In this study, the Neimark-Kiselev (N-K) fractal approach was applied to investigate the heterogeneity in the PSD of the lower Silurian organic-rich shales in South China using low-pressure N2 adsorption, total organic carbon (TOC) content,
maturity analysis, X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) measurements. The results show that (1) the fractal dimension DN-K obtained by N-K theory better represents the heterogeneity of the PSD in shale at an approximately 1–100
nm scale. The DN-K values range from 2.3801 to 2.9915, with a mean of 2.753. The stronger the PSD heterogeneity is, the higher the DN-K value in shale is. (2) The clay-rich samples display multimodal patterns at pore sizes greater than 20 nm, which strongly
effect the PSD heterogeneity. Quartz-rich samples display major peaks at less than or equal to a 10 nm pore size, with a smaller effect on the PSD heterogeneity in most cases. In other brittle mineral-rich samples, there are no obvious major peaks, and a weak heterogeneity of the PSDs is displayed.
(3) A greater TOC content, maturity, clay content and pore size can cause stronger heterogeneity of the PSD and higher fractal dimensions in the shale samples. This study helps to understand and compare the PSD and fractal characteristics from different samples and provides important theoretical
guidance and a scientific basis for the exploration and development of shale gas resources.
Stabilization of Soil Arsenic with Iron and Nano-Iron Materials: A Review
Authors: Yue Changsheng , Du Huili , Li Yan , Yin Naiyi , Peng Ben , Cui Yanshan
Published: November 2020

Soil arsenic (As) contamination is an important environmental problem, and chemical stabilization is one of the major techniques used to remediate soil As contamination. Iron and iron nanoparticle materials are widely used for soil As stabilization because they have one or more of the
following advantages: high adsorption capacity, high reduction capacity, cost effectiveness and environmental friendliness. Therefore, this review introduces the stabilization of soil As with iron and iron nanoparticles, including zero-valent iron, iron oxides/hydroxides, some iron salts and
Fe-based binary oxides and the nanoparticles of these iron materials. The mechanism of chemical soil As stabilization, which involves adsorption and the coprecipitation process, is discussed. The factors affecting the chemical stabilization process are presented, and challenges to overcome
in the future are also discussed in this review.
Relationship Between the Nanopore Structure and Basic Characteristics of Coal with the Protogenetic CO Content
Authors: Tan Bo , Cheng Gang , Yang Xianbing , Zhu Xiaoman , Hu Mingming , Wang Haiyan
Published: November 2020

In the prediction and forecasting of spontaneous coal combustion, protogenetic CO produced in the process of coal oxidation is used as the indicator gas, but the sources of CO gas in coal seams are extensive. Protogenetic CO in coal seams often interferes with predictions of spontaneous
coal combustion. To predict the content of protogenetic CO gas in coal seams and its emission, this study established an experimental system of protogenetic CO content and emission in coal seams. Six groups of coal samples were tested, and the CO emission content was determined per hour within
24 hours of obtaining each coal sample. Four kinds of protogenetic CO gas emission indexes were defined. Then, internal factors of coal, including industrial components, elemental content and pore structure, were analysed. Finally, the relationship between the protogenetic CO gas emission
index of coal seams and the internal factors of coal was obtained. The results indicate that the relation between the CO dispersion concentration and the time of the coal sample follows an exponential power distribution. The internal factors of coal influence the content and emission of protogenetic
CO in coal seams, but there is no strict correlation with each parameter as it is a multi-parameter correlation synthesis process.
Effect of Composition on the Micropore Structure of Non-Marine Coal-Bearing Shale: A Case Study of Permian Strata in the Qinshui Basin, China
Authors: Yu Kun , Ju Yiwen , Yang Yanhui , Qiao Peng , Li Wuyang , Ju Liting , Zhu Hongjian , Huang Cheng , Feng Hongye
Published: November 2020

The nanopore network in organic-rich shale plays a key role in shale gas storage and migration, and micropores are an important structural unit in connecting the migration channel. In this study, we selected six non-marine coal-bearing shales from the Qinshui Basin to investigate the effect of composition on micropore structure using X-ray diffraction, total organic carbon (TOC), vitrinite reflectance, and CO2adsorption methods. The results indicate that non-marine shale with higher TOC content possesses more micropores, leading to a more complex pore structure and improving the heterogeneity of shale reservoirs. With the increase in TOC content, the micropore surface area and micropore volume clearly increases, which greatly improves the gas storage space in shale reservoirs. The thermal evolution of organic matter promotes the development of micropores to a certain extent in non-marine shale. Clay minerals possess a rough surface and develop more micropores, and their influence on the micropore structure of non-marine shale is relatively strong, while terrestrial quartz exhibits significant micropore development. The obviously positive correlations between micropore volume and kaolinite, chlorite contents in the non-marine shale suggest that kaolinite and chlorite make a certain contribution to micropore volume. The characteristics of micropore structures in coal mainly depend on lithotypes, TOC content, and ash content, while clay content, quartz content, and TOC content are the key factors controlling the formation of micropores in non-marine shale.
Micron-Nanometer Evaporite Mineral Compositions in the Jiangling Depression, Jianghan Basin, China, by Means of Scanning Electron Microscopy
Authors: Wang Chun-Lian , Liu Li-Hong , Wang Jiu-Yi , Yu Xiao-Can , Yan Kai
Published: November 2020

Scanning electron microscopy (SEM) was used to analyze and study micron-nanometer evaporite samples collected from Paleocene and Eocene drill cores in the Jiangling Depression. Accordingly, seven beds of potassium-bearing solid rocks were accurately identified. Sylvite, carnallite,
syngenite, dolomite, thenardite, anhydrite, glauberite, halite, barite, celestite, and other solid salt minerals were found, and carnallite, syngenite, and thenardite were found for the first time in the Jiangling Depression. Sylvite, syngenite, and carnallite indicate that the Paleogene salt
lakes in the Jiangling Depression had evolved to the sylvite stage and that prospecting for solid sylvite would be satisfactory. Micron-nanometer celestite is contained in the evaporites, from which we can infer that strontium may have been provided by deep formation water (or oil-field water).
This finding is of great significance to studying the genesis of sylvite sediment in the Jiangling Depression. From the extensive development of primary glauberite beds typical of warm salt minerals in the Shashi Formation, it can be inferred that the late Paleogene paleoclimate in the Jiangling
Depression of the Jianghan Basin was dry and hot. Based on the extensive distribution of micron-nanometer pyrite, siderite, iron and Fe2O3/FeO ratios in evaporite sediments and color analysis of mudstones, the evaporites in the study area formed in an underwater anoxic,
reducing environment during sedimentation. Therefore, the evaporite sediments in the Paleocene–Eocene interval of the Jiangling Depression are proposed to have formed in a saltwater lake sedimentary environment, and the ancient lake was characterized by a deep-water salt lake sedimentary
model.
Micron-Nano Pore Structures and Microscopic Pore Distribution of Oil Shale in the Shahejie Formation of the Dongying Depression, Bohai Bay Basin, Using the Argon-Scanning Electron Microscope Method
Authors: Wu Wei , Wang Guangxu , Liu Gaofeng , Dong Xinjun , Yu Jing , Pan Jienan
Published: November 2020

To investigate the pore structure of shale oil reservoirs, seven organic-rich shales from the Shahejie Formation in the Dongying Depression were studied by rock pyrolysis analysis, X-ray diffraction analysis and scanning electron microscopy with argon ion beam polishing. The proportions
of the different types of pores at different scales, the statistical relationships between the mineral contents and pore development, and the development of pores in the mineral laminae combination were discussed. The results demonstrated that the nanometer to micron pore structures were divided
into intraparticle pores, interparticle pores, intercrystalline pores, organic pores, microfissures and diagenetic contraction fractures. Interparticle pores and intraparticle pores are both essential components of the sample pores. The original residual pores are mainly small pores and mesopores,
while the secondary dissolution pores are primarily mesopores and macropores. For different pore sizes, there are small surface pore contributions of diagenetic contraction fractures, microfissures, intercrystalline pores, and organic pores. The carbonate minerals content controls the oil
storage capacity of shale by dominating the development of the various pore types, while the clay mineral bands content can affect the permeability of shale by influencing the development of large-scale microfissures. In the laminae development sample, surface pore development is closely related
to the sedimentary mineral microcircle, which consists of a falling semicycle and a rising semicircle. The total surface porosity, including microfissures, diagenetic contraction fractures, interparticle pores and intraparticle pores, mainly developed at the intersection of the rising semicircle
and the falling semicircle, and this development corresponds to the highest level of a cycle. In summary, interparticle pores and intraparticle pores are the main components of pores developed in low thermal maturity shale and shale laminae where their heterogeneity is influenced by mineral
composition and laminae microcircles.
Study of Microscopic Structure of Ceramic Materials Prepared from Nonmetallic Mineral Group Associated with Skarn-Type Gold Deposits
Authors: Li Yongli , Huang Fei , Zhang Zhibin , Liu Can , Xu Longhua , Cheng Yunhong
Published: November 2020

The microscopic structure of ceramic bodies has an essential influence on their performance. In this study, a ceramic material was prepared by modifying a nonmetallic mineral group (J) associated with a skarn-type gold mine in Hubei. The nano and microsized structures of the
fired ceramic bodies under different contents of nonmetallic mineral group (J) and varying temperature conditions were systematically observed and tested by scanning electron microscopy (SEM), Malvern laser particle size analysis, differential scanning calorimetry (DSC) and X-ray diffraction
(XRD). The J content affects the sintering and melt degree of the ceramic body, the contact mode of the particles inside the ceramic body and the pore structure. When the content of J is less than 70%, the performance parameters of the sintered body can meet the requirements
of Group AII in the International Standard of Ceramic Tiles. It is concluded that the microscopic structure of the ceramic body is affected by the complex phase transition process including the dehydration, oxidation, melting and recrystallization of nonmetallic minerals during the firing
process and is closely related to the properties of the ceramic body. It is feasible to improving the properties of ceramic bodies by adJusting the gradation parameters of J and increasing the proportion of fine grains under the same dosage. Considering the features of the ceramic
body and J′ utilization ratio, the optimum content of nonmetallic minerals associated with the skarn-type gold deposit in Hubei Province is 68–43%, and the optimum sintering temperature is approximately 1150 °C.
Experimental Evidence and Characteristic Recognition of the Nanoweakening of Slip Deformation Zones
Authors: Sun Yan , Ju Yiwen , Zhou Wei , Chao Hongtai , Wang Zhicai , Wang Lei , Zhu Hongjian , Han Kui
Published: November 2020

A central issue in the study of fault evolution is to identify shear weakening and its mechanism; currently, studies of fault weakening in narrow slip deformation zones, including those of various slipping planes such as schistosity, foliation, cleavage, joints and faults in rocks,
are ongoing. To verify the nanoweakening in shear slipping, we carried out experiments: triaxial compression experiments on sandstones and uniaxial compression experiments on granites. Furthermore, on the basis of scanning electron microscopy (SEM) observations and experimental data analyses,
we suggested three kinds of nanoweakening in terms of the corresponding strain stages: (1) The slip nanoweakening caused by the strain hardening deformation stage of the shear slip, which creates nanograins with dense coatings that may be due to the nanocoating on the shear planes, can result
in rolling friction rather than with sliding friction, and the former is a principal mechanism of sliding nanoweakening. (2) The rheological nanoweakening caused by the strain softening deformation stage; in view of developing weakened deformation due to grain boundary migration (GBM), the
flow of synkinematic minerals and melt coating phenomena lead to rheological nanoweakening. (3) The dynamic nanoweakening caused by thermal pressurization and fluid pressurization during the strain softening stage and strain degenerating stage. Thus, when these aspects are considered in defining
the relationship between the nanoweakening at the slipping planes and the strain stages, the representative mechanism and its behavior rules can be obtained.