Search results

We have seen a considerable effort in colloid sciences to copy Nature’s successful strategies to fabricate complex functional structures through self-assembly. This includes attempts to design colloidal building blocks and their intermolecular interactions, such as creating the colloidal analogs of directional molecular interactions, molecular recognition, host-guest systems, and specific binding.

We describe the synthesis of hybrid magnetic ellipsoidal nanoparticles that consist of a mixture of two different iron oxide phases, hematite (α-Fe2O3) and maghemite (γ-Fe2O3), and characterize their magnetic field-driven self-assembly. We demonstrate that the relative amount of the two phases can be adjusted in a continuous way by varying the reaction time during the synthesis, leading to strongl

Terpene emissions from the top-canopy layer (at 20 m) of one 118-year-old Norway spruce tree were measured between June and September 2013 using a branch chamber. Total terpene emissions varied from 0.05 to 332.5 μg gdw -1 h-1 with a peak in August. Monoterpenes dominated throughout the summer and on average accounted for 65% of the total terpene mass, followed by sesquiterpenes (29%) and isoprene

Purpose: A well-functioning curbside system must consider several properties, such as the location of collection points, from a logistical standpoint to ensure efficient hauling and transportation. The collection point itself should also promote a good working Environment for the collection personnel. However, many older urban areas were not designed with modern logistical and environmental aspect

Purpose: Construction waste is one of the larger waste streams in the developed world. Its environmental impact can be reduced by increased waste sorting. Waste sorting efficiency, however, is influenced by the characteristics of an evolving construction site with space limitation, changing layout, different waste streams over time, and the many different actors involved. This study explores facto

Background Dual-energy computed tomography (DECT) has conceptually been known since the late 1970s and commercially available as dual-source CT (DSCT) systems since 2006; however, the technique has not yet seen widespread implementation in routine protocols. Part of the cause for this is likely due to misconceptions about radiation dose and/or image quality when using DECT. Purpose To compare imag

A model-based predictive controller known as Dynamic Matrix Control with Linear Programming optimizer (DMC-LP) is applied to a nonlinear multivariable laboratory process which consists of four interconnected water tanks. Experimental results show that DMC-LP is a powerful constrained model predictive controller. Based upon simple step response model, it can provide improved control performance and

Globally, waste volumes are increasing rapidly and the World Bank estimates a 70% global increase in municipal solid waste until 2025. Waste may have serious environmental consequences and there is a strong correlation between solid waste generation rates and greenhouse gas emissions. These two observations alone indicate that this development is not sustainable. Recycling is one of the most impor

In 2017,for the first time, more than half of all people living with HIV (PLHIV) had access to antiretroviral treatment (ART). This expansion of ART has in part been achieved through decentralization of HIV care in resource-limited settings. There, many PLHIV now receive care at ART clinics integrated within the primary health care system. At these clinics, non-physician clinicians are responsible

In this paper we briefly discuss the current provisional temperature scale of 2000 (PLTS-2000) for low temperatures. Electronic thermometry is presented and discussed, focusing on its potential in verifying and realizing a future temperature scale. The discussion covers secondary thermometers such as NIS and SIS thermometers and noise, shot noise and Coulomb blockade primary thermometers. The last

The electromagnetic environment of a tunnel junction can influence significantly the tunneling characteristics. We investigate experimentally a particular environment formed by tunnel junctions and compare the results with a theoretical model. We discuss Single Junction Thermometer and a two junction Coulomb Blockade Thermometer as examples.

We describe the concept and experimental demonstration of primary thermometry based on a four-probe measurement of a single tunnel junction embedded within four arrays of junctions. We show that in this configuration random sample specific and environment-related errors can be avoided. This method relates temperature directly to Boltzmann constant, which will form the basis of the definition of te

The authors report a method to achieve Al-Al Ox -Al tunnel junctions with high specific resistance in a controlled manner using a double oxidation technique. The technique is based on the standard method for oxidation repeated on an additional Al layer. The tunnel junctions were characterized with standard methods, such as comparison of room temperature resistance with liquid helium resistance and

A design of sub-Kelvin single-flux quantum (SFQ) circuits with reduced power dissipation and additional cooling of shunt resistors has been developed and characterized. The authors demonstrate operation of SFQ comparators with current resolution of 40 nA at 2 GHz sampling rate. Due to improved cooling the electron temperature in shunt resistors of a SFQ comparator is below 50 mK when the bath temp

A model and experimental results of a new method for exposing bit arrays with electron beam lithography are presented. The method allows the reduction of the amount of pattern data by orders of magnitude. The method utilises two overlapped exposures. In the first exposure a 1-D array of parallel stripes is written and in the second exposure another 1-D array of parallel stripes orthogonal to the f

Many ships today rely on Global Navigation Satellite Systems (GNSS), for their navigation, where GPS (Global Positioning System) is the most well-known. Unfortunately, the GNSS systems make the ships dependent on external systems, which can be malfunctioning, be jammed or be spoofed. There are today some proposed techniques where, e.g., bottom depth measurements are compared with known maps using