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It is well known that sustainability has become a much needed target, especially considering the recent rapid urban sprawl and the subsequent exacerbation of social, environmental, and economic problems. Thus, many studies have been conducted to define sustainability and the sustainable city. However, many of these definitions suggest a range of contradictions, implying that the achievement of sustainability is elusive. The problem lies in setting unreasonable definitions of sustainability and in the various contradictions to these definitions, making sustainability seemingly unattainable. Hence, some models of cities are emerging that are labeled as sustainable cities; among these are the “zero-carbon city” and the “ubiquitous eco-city” (“U-eco-city”). This study reviews the history and definitions of sustainability, in order to acknowledge the contradictions inherent in these concepts. It also briefly presents the compact city, the zero-carbon eco-city, and the U-eco-city by determining their individual pros and cons and highlighting where there are any conflicts with the principles of sustainability. The aim of the study was to adjust the use of sustainability as a terminology in the field of urban sustainable development and to demonstrate the extent to which we use marketing names for eco-cities without compliance with sustainable dimensions. The study will also discuss the key sustainability pillar required for a project to be kept sustainable. The study concludes that the use of the term “sustainable city” may limit the potential for further enhancing sustainability in future projects; using the term “transition toward the sustainable city” may be more accurate and more effective. The results show that reducing energy consumption through efficient use, and relying on renewable energies, will be the keys to reaching urban sustainability. The study also finds that recent tyranny in the name of ecology will not result in real sustainability. Although the free eco-city and the u-eco-city are considered advanced models, their limitations are related more to the economic and social aspects than to the compact city, which clearly reflected the pillars of sustainability, despite its being an outdated model.

Two-dimensional (2D) heterostructure with atomically sharp interface holds promise for future electronics and optoelectronics because of their multi-functionalities. Here we demonstrate gate-tunable rectifying behavior and self-powered photovoltaic characteristics of novel p-GeSe/n-MoSe 2 van der waal heterojunction (vdW HJ). A substantial increase in rectification behavior was observed when the devices were subjected to gate bias. The highest rectification of ~ 1 × 10 4 was obtained at V g  = − 40 V. Remarkable rectification behavior of the p-n diode is solely attributed to the sharp interface between metal and GeSe/MoSe 2 . The device exhibits a high photoresponse towards NIR (850 nm). A high photoresponsivity of 465 mAW −1 , an excellent EQE of 670%, a fast rise time of 180 ms, and a decay time of 360 ms were obtained. Furthermore, the diode exhibits detectivity (D) of 7.3 × 10 9 Jones, the normalized photocurrent to the dark current ratio (NPDR) of 1.9 × 10 10  W −1 , and the noise equivalent power (NEP) of 1.22 × 10 –13 WHz −1/2 . The strong light-matter interaction stipulates that the GeSe/MoSe 2 diode may open new realms in multi-functional electronics and optoelectronics applications.

Supply chain management is described as a business strategy that provides operative management of financial, material, and other information flows to ensure harmonization in distributed organizational structures. The predefined aim of this study was to describe the effects of green supply chain management practices on competitive strategic alliances using automobile firms in China. The study aimed to demonstrate different factors that aid strategic alliances, which automobile firms must acknowledge to improve their performance. Fifty automobile firms were used as the study population. The respondents were senior managers of five active areas in each automobile firm. There were a total of 420 respondents, among whom 320 respondents were selected by the convenience sampling method. The study was quantitative, while the data source was primary; the data were obtained using a closed-ended questionnaire as the major instrument for data collection. This closed-ended questionnaire was sent to the intended respondents via email and WeChat simultaneously. Five active areas were included, and Cronbach’s alpha values were measured for each area. The values obtained ranged from 0.8 to 0.9, revealing the data’s consistency and reliability. The primary data obtained were analyzed using descriptive statistics for demographic data and inferential structural equation modeling (SEM) for multivariate data. Considering the outcomes of the research analysis, it was concluded that forming competitive strategic alliances in firms to manage green supply chains could bring several benefits.

The Pt / rGO nanocatalyst was synthesized by the immobilization method by deposition of platinum nanoparticles on reduced graphene oxide (rGO) as a support material. The support (rGO) was prepared from the reduction of graphene oxide (GO) by the reducing agent sodium borohydride (NaBH4), while (GO) was prepared from the graphite oxidation using the modified Hummer method. Morphological, chemical and structural characteristics of synthesized samples were investigated by Scanning Electron Microscope (SEM), transmittance Scanning Microscope (TEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and X-ray and Raman Spectroscopy. The performance of the Pt/rGO catalysts were evaluated in the benzyl alcohol oxidation to produce benzaldehyde using an environmentally friendly oxidizing agent, hydrogen peroxide, under moderate conditions. The variables that were studied on oxidation of benzyl alcohol were temperature, catalyst mass and H2O2 concentration. The best results were achieved when the catalyst amount was 10 mg, 50% hydrogen peroxide concentration and 80 °C reaction temperature. The conditions under which the reaction was carried out are moderate reaction conditions, and the oxidizing agent (H2O2) is an environmentally friendly oxidizing agent.

Agricultural suitability analysis using traditional methods is still arguable due to the uncertainty and subjectivity resulting from manual evaluations. The current work provides a novel framework for integrating the analytical hierarchy process (AHP) with fuzzy logic under the geographic information system (GIS) platform to generate suitability maps for cultivating wheat, broad bean, and maize under center pivot irrigation systems. The research was executed in an arid region (30229 ha) in the western Nile Delta fringes, Egypt. Meteorological data, digital elevation model, and samples collected from seventy soil profiles and fourteen artesian wells were analyzed to characterize local climate conditions, landscape characteristics, and irrigation water quality. The main and sub-criteria were prone to AHP to specify the relative importance (weight) of each factor. Using GIS tools, raster layers were created, assigned scores (fuzzy membership functions) according to crop requirements, and complied in accordance with the weighted sum algorithm to produce final crop suitability maps. Results revealed that climate conditions were highly (S1) and moderately (S2) suitable for winter crops (wheat and broad bean) but marginally suitable (S3) for summer crop (maize). Soil salinity, sodicity, and depth were the most important determinants of landscape suitability. Accordingly, the land resources in the studied region were suitable (S1, S2, and S3) for the selected crops; nevertheless, 193 and 275 ha were currently not suitable (N1) for broad bean and maize, respectively. Potential salinity and specific ion (sodium and chloride) toxicity hazards were the main constraints for groundwater irrigation. The center pivot irrigation would meet wheat and maize requirements but adversely affect broad bean yield. Overall, groundwater quality contributed to 46% of site suitability for crop production followed by landscape factors that contributed to 42% and climate conditions that accounted for 13%. The final suitability maps affirmed high priority for wheat cultivation in the studied region since the S1 and S2 classes encompassed 90 and 10%, respectively. Moreover, maize ranked as the second suitable crop with 55, 42, and 35 of the total area fitting the S1, S2, and S3 classes, respectively. The third place was due to broad bean with S2 and S3 classes representing 53 and 47% of the total area, respectively. Our study can offer a replicable framework to integrate AHP with GIS-fuzzy logic for sustainable food crop production in drylands.

Investigating the promising chalcogenide materials for the development of memory and advanced neuromorphic computing applications is a critical step in realizing electronic memory and synaptic devices that can efficiently emulate biological synaptic functions. However, the assessment of monochalcogenide materials for the fabrication of highly scalable memory and electronic synaptic devices that can accurately mimic synaptic functions remain limited. In the present study, we investigated the thickness-dependent resistive switching (RS) behavior of conductive bridge random access memory (CBRAM) based on a monochalcogenide GeSe switching medium for its possible application in high-performance memory and electronic synapses. GeSe thin films of different thicknesses (6, 13, 24, 35, 47, and 56 nm) were deposited via sputtering to fabricate CBRAM devices with a stacking sequence of Ag/GeSe/Pt/Ti/SiO 2 . The devices exhibited compliance current (CC)-free and electroforming-free RS with highly stable endurance and retention characteristics with no major degradation. All devices with a thickness of 6 nm had a low-resistance state (LRS), which required an initial reset to ensure reliable switching cycles. The devices with a thickness of 47 nm and above exhibited the co-existence of unipolar resistive switching (U-RS) and bipolar resistive switching (B-RS) with the CC-controlled transition between the two switching behaviors. Multilevel resistance states in the 24-nm device between a highresistance state (HRS) and an LRS were achieved by controlling the set-CC (from 5 mA to CC-free) and the reset stop voltage (from −0.5 to −1.0 V) during the set and reset processes, respectively. The analog RS behavior of the device was further investigated with appropriate pulse measurements to emulate vital synaptic functions, including long-term potentiation (LTP), long-term depression (LTD), spike-rate-dependent plasticity (SRDP), spike-timing-dependent plasticity (STDP), paired-pulse facilitation (PPF), paired-pulse depression (PPD) and post-tetanic potentiation (PTP). Overall, the detailed investigation of thickness-dependent GeSe monochalcogenide material indicates that it is a highly suitable candidate for use in highly scalable memory devices and electronic synapses for neuromorphic computing applications.

The presence of dyes in water is the most popular problem recently, so the current study was directed towards the synthesis of an effective material consisting of NiO and MWCNTs. The NiO/F-MWCNTs nanocomposite was synthesized using a simple hydrothermal method after functionalization of MWCNTs using sulfuric acid and nitric acid and utilized as an efficient surface to adsorption of malachite green dye from polluted water. The nanocomposite sample was characterized using several techniques are X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), Field emission scanning electron microscopy (FESEM), High- resolution transmission electron microscopy (HRTEM), Brunauer–Emmett–Teller (BET) surface area analysis, Barrett-Joyner-Halenda (BJH) analysis and Energy dispersive X-ray (EDX). The analytical results showed that the prepared nanocomposite is of good crystalline nature with a particle size of 25.43 nm. A significant specific surface area was 412.08 m 2 /g which indicates the effective impact of the nanocomposite in the adsorption of malachite green (MG) dye. On the other hand, the effect of adsorbent dose, temperature, acidic function and contact time on the adsorption efficiency of dye was studied. The kinetics of dye adsorption were also investigated employing two kinetic models, pseudo-first-order model and pseudo-second-order model. Finally, the thermodynamic functions were determined to identify the type of the reaction and the spontaneity of the process.

Cost-effective simultaneous determination of mercury, copper and cadmium ions was performed by differential pulse anodic stripping voltammetry (DPASV) using a pencil graphite electrode (PGE) modified with poly-L-cysteine (P-L-Cys) and Fe 3 O 4 nanoparticles. Electropolymerization of L-cysteine was performed by cyclic voltammetry (CV) through applying different cycles. Also, Fe 3 O 4 was deposited in a single step by applying a constant potential on the electrode surface in the presence of ferric nitrate. To enhance the sensitivity of measurement, several parameters such as monomer concentration, scan rate, number of cycles in electropolymerization, ferric nitrate concentration, Fe 3 O 4 electrodeposition potential and time, and pH of the sample solution were optimized. The surface morphology of the modified electrode was examined by SEM and FTIR. Electrochemical impedance spectroscopy was conducted to investigate the impedance of the electrode surface. The linear ranges for cadmium, copper and mercury were 0.001‒2500, 0.0002‒3600 and 0.0001‒2500 nM with detection limits of 6.4 × 10 –13 , 1.0 × 10 –13 and 9.0 × 10 –14  M, respectively. The stability and reproducibility of the electrode were investigated. Finally, the modified electrode was applied to determine mercury, copper and cadmium in real samples such as the groundwater, Caspian Sea and Tajan River water. Graphical abstract

Expansive soils are usually classified as problematic soils. These soils have a tendency to absorb water and expand causing damages to light weight structures and buildings. To control these changes in volume, different measures have been proposed. Under reamed pile is considered as good foundation techniques to mitigate swelling result from the expansive soils. The effort of this study is to estimate uplift movement response of under reamed pile in this soil. The influence of various parameters like length of under reamed pile (L), number of bulbs and extended length of under reamed pile in sandy soil are investigated. Many findings are obtained from this work that showed ability of under reamed pile in mitigating the uplift movement of expansive soil. There are three dominated independent variables of uplift movement of under reamed pile; number of bulbs, slenderness ratio (L/D) ratio and extended length in sandy soil. The uplift movement is lessened to (93%) when (under reamed pile of single bulb) embedded in expansive soil layer and extended to sandy soil at (L/H = 1.46) and decreased by about (96%) when (under reamed pile of double bulbs) embedded in expansive soil and extended to sandy soil at (L/H = 1.5).