bluuebunny/crossref_metadata_2025_split huggingface dataset:
Persistence of the Nb(100) surface oxide reconstruction at elevated temperatures
Authors: McMillan Alison A , Graham Jacob D , Willson Sarah A , Farber Rachael G , Thompson Caleb J , Sibener S J 
Published: September 2020

Abstract
Helium atom scattering and Auger electron spectroscopy (AES) are used to characterize the (3 × 1)-O reconstruction of the Nb(100) surface at elevated temperatures. Persistent helium diffraction peaks and specular lineshape analysis indicate that the oxide structure persists, apparently unchanged, until surface temperatures of at least 1130 K. In a complementary experiment, AES oxygen to niobium ratios for Nb(100) show little to no change when the surface temperature is varied from 300 K to 1150 K. These data inform future development of superconducting radio frequency (SRF) cavities. In particular, these findings demonstrate the important role that persistent niobium oxides will play in the optimization of thin film growth strategies and coating procedures for Nb3Sn and other next–generation SRF superconducting alloy materials.
Fast and efficient critical state modelling of field-cooled bulk high-temperature superconductors using a backward computation method
Authors: Zhang Kai , Ainslie Mark , Calvi Marco , Hellmann Sebastian , Kinjo Ryota , Schmidt Thomas 
Published: September 2020

Abstract
A backward computation method has been developed to accelerate modelling of the critical state magnetization current in a staggered-array bulk high-temperature superconducting (HTS) undulator. The key concept is as follows: (i) a large magnetization current is first generated on the surface of the HTS bulks after rapid field-cooling (FC) magnetization; (ii) the magnetization current then relaxes inwards step-by-step obeying the critical state model; (iii) after tens of backward iterations the magnetization current reaches a steady state. The simulation results show excellent agreement with the
H
-formulation method for both the electromagnetic and electromagnetic-mechanical coupled analyses, but with significantly faster computation speed. The simulation results using the backward computation method are further validated by the recent experimental results of a five-period Gd–Ba–Cu–O (GdBCO) bulk undulator. Solving the finite element analysis (FEA) model with 1.8 million degrees of freedom (DOFs), the backward computation method takes less than 1.4 h, an order of magnitude or higher faster than other state-of-the-art numerical methods. Finally, the models are used to investigate the influence of the mechanical stress on the distribution of the critical state magnetization current and the undulator field along the central axis.
Optoelectronic and photocatalytic properties of I–III–VI QDs: Bridging between traditional and emerging new QDs
Authors: Liu Yanhong , Li Fenghua , Huang Hui , Mao Baodong , Liu Yang , Kang Zhenhui 
Published: September 2020

Abstract
Due to the quantum size effect and other unique photoelectric properties, quantum dots (QDs) have attracted tremendous interest in nanoscience, leading a lot of milestone works. Meantime, the scope and scientific connotation of QDs are constantly expanding, which demonstrated amazing development vitality. Besides the well-developed Cd-containing II–VI semiconductors, QDs of environmentally friendly I–III–VI (I = Cu, Ag; III = Ga, In; VI = S, Se) chalcogenides have been a hot spot in the QDs family, which are different from traditional II–VI QDs in terms of multi-composition, complex defect structure, synthetic chemistry and optical properties, bringing a series of new laws, new phenomena and new challenges. The composition of I–III–VI chalcogenides and their solid solutions can be adjusted within a very large range while the anion framework remains stable, giving them excellent capability of photoelectric property manipulation. The important features of I–III–VI QDs include wide-range bandgap tuning, large Stokes shift and long photoluminescence (PL) lifetime, which are crucial for biological, optoelectronic and energy applications. This is due to the coexistence of two or more metal cations leading to a large number of intrinsic defects within the crystal lattice also known as deep-donor-acceptor states, besides the commonly observed surface defects in all QDs. However, a profound understanding of their structure and optoelectronic properties remains a huge challenge with many key issues unclear. On one hand, the achievements and experience of traditional QD research are expected to provide vital value for further development of I–III–VI QDs. On the other hand, the understanding of the emerging new QDs, such as carbon and other 2D materials, are even more challenging because of the dramatically different composition and structure from II–VI semiconductors. For this, I–III–VI QDs, as a close relative to II–VI QDs but with much more complex composition and structure variation, provide a great opportunity as a gradual bridge to make up the big gap between traditional QDs and emerging new QDs, such as carbon dots. Here, we hope to compare the research progress of I–III–VI QDs and II–VI QDs, in an effort to comprehensively understand their structure, synthetic chemistry, optical electronic and photocatalytic properties. We further give insights on the key potential issues of I–III–VI QDs from the perspective of bridging between traditional QDs and emerging carbon dots, especially the profound principles behind synthetic chemistry, PL mechanism and optoelectronic applications.
Perylene diimide self-assembly: From electronic structural modulation to photocatalytic applications
Authors: Wei Weiqin , Ouyang Shuxin , Zhang Tierui 
Published: September 2020

Abstract
As an emerging organic semiconductor, perylene diimide (PDI) self-assembly has attracted tremendous attention in the aspects of solar cells, sensors, fluorescence probes and n-transistors, etc. In term of photocatalysis, various photocatalysts based on PDI self-assembly exhibit some unique properties, such as intrinsic Π-Π stacking structure, fast internal charge transfer, band-like electronic structure, flexible structural modifiability, well-defined morphological adjustability and excellent light absorption. This paper mainly presents recent progress on PDI self-assembly regarding how to regulate the electronic structure of PDI self-assembly. In addition, the photocatalytic applications of PDI self-assembly and its complexes were reviewed, such as environmental remedy, energy productions, organic synthesis and photodynamic/photothermal therapy, further highlighting related photocatalytic mechanisms. Finally, the review contents and some perspectives on photocatalytic research of PDI self-assembly were summarized, and some key scientific problems were put forward to direct related photocatalytic research in future.
Highly-rough surface carbon nanofibers film as an effective interlayer for lithium–sulfur batteries
Authors: Zhu Hongfan , Sha Mo , Zhao Huaping , Nie Yuting , Sun Xuhui , Lei Yong 
Published: September 2020

Abstract
Lithium–sulfur (Li–S) battery with a new configuration is demonstrated by inserting a flexible nitrogen-doping carbon nanofiber (N-CNFs) interlayer between the sulfur cathode and the separator. The N-CNFs film with high surface roughness and surface area is fabricated by electrospinning and a subsequent calcination process. The N-CNFs film interlayer not only effectively traps the shuttling migration of polysulfides but also gives the whole battery reliable electronic conductivity, which can effectively enhance the electrochemical performance of Li–S batteries. Finally, Li–S batteries with long cycling stability of 785 mAh/g after 200 cycles and good rate capability of 573 mAh/g at 5 C are achieved.
Improving Shallow-Deep Foundation with Reinforcement by Geogrids for Tall Building
Authors: Al-Laban H. E. , Fakhraldin M. K. 
Published: September 2020

Abstract
This research has studied the effect of the vertical load, it has acted at the center of the raft foundation and piled raft foundation. Stresses resistance and displacements were significant parts to examine the behavior of improving foundation. These are important parts of life the structure. The study focuses on different cases of the embedded layer in tension zone with concrete grade B20 of (MD/XMD) Tensor SS2 geogrids in raft and piled raft foundation for a tall building in Incheon Tower in South Korea, it was treated to solve those problems. Stresses resistance of raft and piled raft foundation were greater than vertical stress applied of dead and live loads, also the stress value of XMD was greater than the value of MD.
Comparison of Single and Group Jet Grout Columns Settlement Based on Field Test and Theoretical Methods
Authors: Al-Kinani Ali M. , Ahmed Mahmood D. 
Published: September 2020

Abstract
The settlement evaluation for the jet grouted columns (JGC) in soft soils is a problematic matter, because it is influenced by the number of aspects such as soil type, effect mixture between soil and grouting materials, nozzle energy, jet grouting, water flow rate, rotation and lifting speed. Most methods of design the jet-grouting column based on experience. In this study, a prototype single and group jet grouting models (single, 1*2, and 2*2) with the total length and diameter were (2000 and 150 mm) respectively and clear spacing (3D) has been constructed in soft clay and subjected to vertical axial loads. Furthermore, different theoretical methods have been used for the estimation of (JGC) settlement. Pile load settlement analysis of the jet grout columns showed that the average settlement values were (0.41, 0.663, and 1.5 mm) for the single, group (1*2) and group (2*2) jet grouted columns respectively. While, in the theoretical methods give a higher value of the settlement (2.0, 3.48, and 5.24 mm) for the single, group (1*2) and group (2*2) jet grouted columns compared with the settlement results acquired from field pile load test data. Therefore, it is not recommended to be used for soft clay. On the other hand, Fuller and Hoy’s, Hansen’s 90%, and Butler and Hoy’s results may be considered faithful interpretation methods for the single and group (1*2 and 2*2) (JGC).
Numerical Simulation of Predicting the Shaft Capacity of Single Pile in Unsaturated Soil
Authors: Albusoda Bushra S. , Abbas Mohammad F. , Al-Hamdani Durgham A. 
Published: September 2020

Abstract
Pile foundations that placed above the groundwater table zone where the soil is typically in a state of the partially saturated case have been considered in this study. To appreciate the effect of the matric suction on the skin resistance of single pile foundations that placed in unsaturated clayey soil. A series of small scale and full-scale single model pile are simulated using the software Plaxis 3 D. Mohr-Coulomb model (Elastic-perfectly plastic model) that takes into account the effect of the matric suction has adopted in the analysis. Also, in this study comparison among numerical models and laboratory, small scale single and full-scale pile models have done. In general, the value of shaft capacity obtained by the numerical investigations are in good agreement with laboratory model pile test results.
Strength and Compressibility of Screw Piles Constructed in Gypseous Soil
Authors: Mukhlef Omar J. , Karkush Mahdi O. , Zhussupbekov Askar 
Published: September 2020

AbstractThe present work deals with the performance of screw piles constructed in gypseous soil of medium relative density; such piles are extensively used in piles foundations supported structures subjected to axial forces. The carrying capacity and settlement of a single screw pile model of several diameters (20, 30, and 40) mm inserted in gypseous soil is investigated in the present study. The gypsum content of soil used in tests was 40%. The bedding soil used in tests was prepared by raining technique with a relative density of 40%. A physical model was manufactured to demonstrate the tests in the laboratory. The model of screw pile has been manufactured of steel with a total length of 500 mm and helix diameters of 20, 30, and 40 mm continuous over the embedded depth of pile (400 mm). The results of tests showed decreasing the ratio of length to diameter (L/D) resulted in a higher axial carrying capacity of screw piles and low corresponding settlement.
Comparison among Different Methods to Estimate Ultimate Capacity of Bored Pile
Authors: Albusoda Bushra S. , Mohammed S. M , Abbas Mohammad F. 
Published: September 2020

Abstract
This study investigates the ultimate load capacity of concrete 1.5 m diameter bored pile based on three methods: field-loading test, field Standard Penetration Test results, and numerical modeling. A comparison of the ultimate load capacities from these methods was made (the measured large-scale field-loading test, the correlated SPT N values applying Novo SPT software and numerical modeling where Plaxis3D software with Mohr-Coulomb model was utilized). The result of the pile field-loading test was more accurate than the other methods and used as a reference for comparison among their results. In general, the value of ultimate load capacity calculated from Novo SPT software and that obtained from numerical analysis were compatible in comparison with field load results.
Effects of Soil-structure Interaction and Different Simulation on the Response of Concrete Box Culverts
Authors: Al-Zaidee Salah R. , Alsalmani Ashraf Hameed , Salam Alhusain 
Published: September 2020

Abstract
This paper shows how different simulation and soil-structure interaction can affect the response of concrete culverts embedded in dry cohesionless soils. Three simulations have been considered. In the first, second, and third simulations, the applied loads have been determined based on empirical relations of PCA without including the soil-structure interaction. The differences between these simulations are in using the beam element for the first one while using the frame element for the second one and the plane strain element for the third one. In addition to neglect the soil-structure interaction, the axial and shear deformations have been neglected in the first simulation. The axial deformations have been included in the second simulation; finally, all of the axial and shear deformations are included in the third simulation.
Two-Way Bubbled Slabs Strengthened by Prestressing Strands
Authors: Al-Rashedi Durai H. , Al-Ahmed Ali H. Ali 
Published: September 2020

Abstract
Nine proposed two-way simply supported slabs were numerically tested by finite element method using ABAQUS commercial software to investigate the behavior of two-way slabs strengthened by prestressing strands, one-third of them were solid and the other two-third were bubbled. All slabs have the same dimensions of (1600 ×1600 ×140) mm. Some of these specimens were strengthened by using two or three strands with nominal diameter (6.4) mm in both directions. The slabs were divided into three groups depending on the type of slab (solid or bubbled) and the bubble diameter to slab thickness ratios (D/H). From the numerical tests, it was found that the ultimate load capacity for the bubbled slab at D/H ratio 0.64 and 0.80 was decreased to 12.6 and 14% respectively, while, the maximum deflection for bubbled slab at D/H ratio 0.64 and 0.8 was increased to 3-4 times as compared with the conventional solid slab.
Analysis of Hyperspectral Remote Sensing Images for Extraction Geological Rock Types Maps by Geospatial Techniques
Authors: Hussein Sabah Jaber , Fakhri Merzah Zainab 
Published: September 2020

Abstract
Hyperspectral images involve a wealth of data, but interpreting them needs an understanding of exactly what properties of ground materials that it is trying to measure and how to relate to the measurements made by the hyperspectral sensor. The purpose of the study is to use hyperspectral remote sensing data for finding of geological locations and the creation of geological rock types map. In this research, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image has been used and analyzed using geospatial techniques such as ENVI software. These techniques include: enhancement, de-correlation stretch, band ratio and classification. All these techniques have been performed to produce geological rock kinds map. Also, 3D surface for ASTER data can be displayed using ENVI software.
Employ 6D-BIM Model Features for Buildings Sustainability Assessment
Authors: Habib Hussain M. , Kadhim R. Erzaij 
Published: September 2020

Abstract
To translate sustainable concepts into sustainable structure, there is a require a collaborative work and technology to be innovated, such as BIM, to connect and organize different levels of industry e.g. decision-makers, contractors, economists, architects, urban planners, construction supplies and a series of urban planning and strategic infrastructure for operate, manage and maintain the facilities. This paper will investigate the BIM benefits as a project management tool, its effectiveness in sustainable decision making, also the benefit for the local industry key stakeholders by encouraging the BIM use as a project management tool to produce a sustainable building project. This paper presented a basic idea about the Building Information Model (BIM) technique and explain the levels of BIM and its dimension, the potential of BIM in sustainability design and the role of BIM in sustainability aspects had been discussed. The role of BIM in the planning and design stages explained the BIM role in sustainability rating system and grant credits in classification processes. Processing of creating 6D had been detailly explaining starting from the framework (ISO 1440) which adopted in the processing of establishing 6D complete system, phases of this system, and development steps from 3D to 4D, 4D to 5D and 5D to 6D. The 6D model features in the sustainability buildings had been explained in this research. As a result, many conclusions have been reached, the most important is there are still significant constraints in adopting of the integration approach between the (BIM) technology with sustainability in Iraqi buildings projects, both are facing great challenges in terms of economic, technical and the awareness level of government and society.
The Factors Affecting on Earned Value Management
Authors: Rezouki Sedqi Esmaeel , Mortadha Sabreen Baqer 
Published: September 2020

Abstract
Earned price management (EVM) is an associate degree business customary for observance the performance of in progress comes. The performance baseline is about up within the coming up with part to live any time and value deviations throughout project execution. EVM solely focuses on the project schedule (SPI) and value (CPI), and doesn’t address alternative vital aspects of quality, Risk, safety and social factors. Therefore, this paper will explain the statistical study aims to know the most important factors that affect in implementation of EVM in a construction project in Iraq and it will be consisting of two main tools which are the assessment of the questionnaire and checklist to obtain real weights affecting the Iraqi construction projects. There is a need for understanding all affecting factors on estimate at completion in EVM. This will develop the equation of EVM. It will be necessary to study affecting factors to achieve major factors of EVM. Based on previous studies and interviews, 207 influential factors were identified. After the first questionnaire, the number was reduced to 73. Based on the interviews with experts, weights were determined and the most influential factors were 37 and were adopted as a checklist.
Analyzing the Obstacles of Investment Process in Iraq Using (5 Whys) and Focus Group Discussion (FQD) Techniques
Authors: Jaber Asmaa M. , Burhan Abbas M. 
Published: September 2020

Abstract
The Iraqi government faces fluctuations in the investment process with oil revenues of the country and other revenues as these revenues cover only the operational budget and salaries of employees. The government seeks to overcome the financial crisis that hit the country through investment and privatization of some projects. The Iraqi plan for sustainable development (2030) Launched by the Ministry of Planning. But the implementation of this plan collides with a series of obstacles. This research aims to analyze the obstacles facing investment projects by using several approved techniques in managing construction engineering projects such as (5 whys) and (FGD) techniques. The open questionnaire was the theoretical source that the researcher adopted to arrive at to identify obstacles, which is conducting personal interviews and field visits and asking several questions to a group of experts in the Investment Authority through which (15) a obstacles was reached that caused delays in the implementation of construction investment projects. The most prominent of these obstacles was routine and slowed procedures Admin. The responses of the experts were arranged in a closed questionnaire form and distributed to the research sample for which a statistical analysis was conducted. These obstacles were arranged based on the importance of relativity in descending order. The researcher concluded that there is a benefit from using techniques that help analyze constraints such as (5 whys) through reaching the main roots and technique (FGD) is a panel discussion for several experts to arrive at through which corrective actions are possible.
Application of Root Causes Analysis Techniques in The Contractor Selection for Highway Projects
Authors: Ahmed Mustafa I. , Rezouki Sedqi Esmaeel 
Published: September 2020

Abstract
Highway projects are one of the most important projects in this decade in Iraq. Highway projects suffer from corruption factors in the contractor selection phase. To succeed in transparency and best value contractor selection for awarding procedure for highway projects, the researcher used root cause analysis techniques to specify the main factors that lead to bad selection for the highway projects in Iraq. Many tools techniques used for the root cause analysis techniques like Fishbone, Pareto chart, and 5-Why. This study conducts the causes of bad contractor selection and analysis by root cause analysis techniques, Pareto chart conducted that internal relationships and administrative corruption are the main causes that covered near than 80% of the problem, and 5-Why conducted that the acceptance of the lowest price is the main cause for bad selection.
Achieving the Benefits and Requirements of Integrated Project Delivery Method Using BIM
Authors: Salim Mahdi S. , Raoof Mahjoob Ahmed Mohammed 
Published: September 2020

Abstract
Through the last decade, Integrated Project Delivery (IPD) methodology considers one of the new contractual relations that are also on the way to further integrate the process of combining design and instruction. On the other hand, Building Information Modeling (BIM) made significant advancements in coordinating the planning and construction processes. It is being used more often in conjunction with traditional delivery methods. In this paper, the researcher will present the achievement of IPD methodology by using BIM through applying on the design of the financial commission building in Mayssan Oil Company in Iraq. The building has not been constructed yet and it was designed by using 2D CAD drawings. The researcher will redesign the project by using BIM to eliciting the abilities that are consistent with the requirements and benefits of integrated project delivery (IPD). The results show that BIM is an appropriate technology that can be used with the IPD method because it has achieved most of the requirements and benefits of IPD.