There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

An Introduction to Composite Materials: Fabrication

The GPR (Ground Penetrating Radar) conference in Hong Kong year 2016 marked the 30th anniversary of the initial meeting in Tifton, Georgia, USA on 1986. The conference has been being a bi-annual event and has been hosted by sixteen cities from four continents. Throughout these 30 years, researchers and practitioners witnessed the analog paper printout to digital era that enables very efficient collection, processing and 3D imaging of large amount of data required in GPR imaging in infrastructure. GPR has systematically progressed forward from “Locating and Testing” to “Imaging and Diagnosis” with the Holy Grail of ’Seeing the unseen’ becoming a reality. This paper reviews the latest development of the GPR’s primary infrastructure applications, namely buildings, pavements, bridges, tunnel liners, geotechnical and buried utilities. We review both the ability to assess structure as built character and the ability to indicate the state of deterioration. Finally, we outline the path to a more rigorous development in terms of standardization, accreditation, and procurement policy.

A review of Ground Penetrating Radar application in civil engineering: A 30-year journey from Locating and Testing to Imaging and Diagnosis

Hydrogels based on cellulose comprising many organic biopolymers including cellulose, chitin, and chitosan are the hydrophilic material, which can absorb and retain a huge proportion of water in the interstitial sites of their structures These polymers feature many amazing properties such as responsiveness to pH, time, temperature, chemical species and biological conditions besides a very high-water absorption capacity Biopolymer hydrogels can be manipulated and crafted for numerous applications leading to a tremendous boom in research during recent times in scientific communities With the growing environmental concerns and an emergent demand, researchers throughout the globe are concentrating particularly on naturally derived hydrogels due to their biocompatibility, biodegradability and abundance Cellulose-based hydrogels are considered as useful biocompatible materials to be used in medical devices to treat, augment or replace any tissue, organ, or help function of the body These hydrogels also hold a great promise for applications in agricultural activity, as smart materials and some other useful industrial purposes This review offers an overview of the recent and contemporary research regarding physiochemical properties of cellulose-based hydrogels along with their applications in multidisciplinary areas including biomedical fields such as drug delivery, tissue engineering and wound healing, healthcare and hygienic products as well as in agriculture, textiles and industrial applications as smart materials

/pdf/cellulose-based-hydrogel-materials-chemistry-properties-and-1k0tgl796u.pdf

Cellulose-based hydrogel materials: chemistry, properties and their prospective applications

Summary Background Alcohol use has increased globally, with varying trends in different parts of the world. This study investigates gender, age, and geographical differences in the alcohol-attributable burden of disease from 2000 to 2016. Methods This comparative risk assessment study estimated the alcohol-attributable burden of disease. Population-attributable fractions (PAFs) were estimated by combining alcohol exposure data obtained from production and taxation statistics and from national surveys with corresponding relative risks obtained from meta-analyses and cohort studies. Mortality and morbidity data were obtained from the WHO Global Health Estimates, population data were obtained from the UN Population Division, and human development index (HDI) data were obtained from the UN Development Programme. Uncertainty intervals (UIs) were estimated using a Monte Carlo-like approach. Findings Globally, we estimated that there were 3·0 million (95% UI 2·6–3·6) alcohol-attributable deaths and 131·4 million (119·4–154·4) disability-adjusted life-years (DALYs) in 2016, corresponding to 5·3% (4·6–6·3) of all deaths and 5·0% (4·6–5·9) of all DALYs. Alcohol use was a major risk factor for communicable, maternal, perinatal, and nutritional diseases (PAF of 3·3% [1·9–5·6]), non-communicable diseases (4·3% [3·6–5·1]), and injury (17·7% [14·3–23·0]) deaths. The alcohol-attributable burden of disease was higher among men than among women, and the alcohol-attributable age-standardised burden of disease was highest in the eastern Europe and western, southern, and central sub-Saharan Africa regions, and in countries with low HDIs. 52·4% of all alcohol-attributable deaths occurred in people younger than 60 years. Interpretation As a leading risk factor for the burden of disease, alcohol use disproportionately affects people in low HDI countries and young people. Given the variations in the alcohol-attributable burden of disease, cost-effective local and national policy measures that can reduce alcohol use and the resulting burden of disease are needed, especially in low-income and middle-income countries. Funding None.

National, regional, and global burdens of disease from 2000 to 2016 attributable to alcohol use: a comparative risk assessment study.

In most water distribution systems, a fairly sizable amount of water is lost because of leaks and faults in pipes. For this reason, the individuation of leaks is extremely important for the optimization and rationalization of water resources. However, the techniques and methodologies that are currently used for the individuation of leaks, despite being universally accepted, are extremely time-consuming and require highly-experienced personnel. Additionally, such techniques become unreliable and ineffective when the measurements are not performed in specific operating conditions of the pipe (e.g., high water pressure). On this basis, in this paper, a time domain reflectometry (TDR)-based system for the non-invasive detection of leaks in underground metal pipes is presented. Not only does the adoption of the developed system leads to accurately pinpoint the leak, but it also allows to dramatically reduce the required inspection times. The TDR-based system for leak detection is described in detail (with particular attention to the measurement principle behind the method and to the methodology). Furthermore, a strategy for enhancing the accuracy in pinpointing the leak is addressed. The proposed system is validated through experimental campaign that consisted in carrying out a leak-detection survey through the traditional methods and through the proposed method.

A New Method for Detecting Leaks in Underground Water Pipelines

In this work, an innovative cellulose-based superabsorbent polymer (SAP) was experimentally assessed as an environmentally friendly alternative to acrylate-based SAPs, for the optimization of water consumption in agriculture. The cellulose-based SAP was synthesized and tested for its swelling capability in different aqueous media. The effectiveness of the SAP in agricultural applications was then evaluated by analyzing its performance after several absorption/desorption cycles, over a period of approximately 80 days, upon addition to different types of soil, i.e., white and red soil, for the cultivation of two varieties of plants typical of the Mediterranean area (tomatoes and chicory). The results confirmed that SAP-amended soil can store a considerable amount of water and can release it gradually to the plant roots when needed. The adoption of the proposed SAP in cultivations could thus represent a promising solution for the rationalization of water resources, especially in desert areas.

https://www.mdpi.com/2073-4441/6/7/2056/pdf

Experimental Assessment of the Use of a Novel Superabsorbent polymer (SAP) for the Optimization ofWater Consumption in Agricultural Irrigation Process

Quality and anti-adulteration control of vegetable oils through microwave dielectric spectroscopy

In this work, three different techniques, namely time domain reflectometry (TDR), ground penetrating radar (GPR) and electrical resistivity tomography (ERT) were experimentally tested for water leak detection in underground pipes. Each technique was employed in three experimental conditions (one laboratory or two field experiments), thus covering a limited but significant set of possible practical scenarios. Results show that each of these techniques may represent a useful alternative/addition to the others. Starting from considerations on the obtained experimental results, a thorough analysis on the advantages and drawbacks of the possible adoption of these techniques for leak detection in underground pipes is provided.

Time domain reflectometry, ground penetrating radar and electrical resistivity tomography: A comparative analysis of alternative approaches for leak detection in underground pipes

In the last twenty years, there has been a sharp increase in the consumption of commodities with a short life-cycle This is especially true for electronic equipment such as mobile phones, which are the focus of this paper The short lifespan, which is due to continually substituting obsolete equipment with newer and more innovative models, has stimulated the growth in sales of these electronic goods Europe continues to be the main mobile phone market in developed countries, but this growth has slowed down over the last two years Despite being an already mature market, Italy has a “diffusion rate” (ie, the number of active lines per 100 inhabitants) higher than 146, which is the highest in the European Union This scenario demonstrated the need for a study examining the sustainability of the mobile phone sector according to two critical aspects that are often due to the behavioural patterns of the users: the first is the energy consumption of mobile phones and their associated equipment, and the second is related to the conflicting link between potential dematerialisation due to the miniaturisation of the devices and the resource consumption and waste generated in this sector This paper discusses these two critical aspects and presents an overview of the Italian mobile phone sector, particularly related to the energy consumption during the use phase and increase of mass flows due to the devices circulating in Italy and the higher amount of the disposable products that have to be managed The results show that, in Italy, the entire mobile phone system consumes approximately 2200 GWh per year, which is equal to 07% of the national electricity consumption, and produces potential e-waste from end-of-life devices totalling over 11 thousand tonnes for the period from 2007 to 2012 Concerning the issue of resources consumption, this estimate highlights that the potential savings in inputs, due to the reduction in device weight over time, has always been counteracted by their increasing demand

Andrea Cataldo

Papers

A New Method for Detecting Leaks in Underground Water Pipelines

Experimental Assessment of the Use of a Novel Superabsorbent polymer (SAP) for the Optimization ofWater Consumption in Agricultural Irrigation Process

Quality and anti-adulteration control of vegetable oils through microwave dielectric spectroscopy

Time domain reflectometry, ground penetrating radar and electrical resistivity tomography: A comparative analysis of alternative approaches for leak detection in underground pipes

A critical analysis of the sustainability of mobile phone use