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The efficient and reliable monitoring of the flow of water in open channels provides useful information for preventing water slow-downs due to the deposition of materials within the bed of the channel, which might lead to critical floods. A reliable monitoring system can thus help to protect properties and, in the most critical cases, save lives. A sensing system capable of monitoring the flow conditions and the possible geo-environmental constraints within a channel can operate using still images or video imaging. The latter approach better supports the above two features, but the acquisition of still images can display a better accuracy. To increase the accuracy of the video imaging approach, we propose an improved particle tracking algorithm for flow hydrodynamics supported by a machine learning approach based on a convolutional neural network-evolutionary fuzzy integral (CNN-EFI), with a sub-comparison performed by multi-layer perceptron (MLP). Both algorithms have been applied to process the video signals captured from a CMOS camera, which monitors the water flow of a channel that collects rain water from an upstream area to discharge it into the sea. The channel plays a key role in avoiding upstream floods that might pose a serious threat to the neighboring infrastructures and population. This combined approach displays reliable results in the field of environmental and hydrodynamic safety.

The measurement of ultra-weak magnetic fields with nanometer-scale spatial resolution is a powerful tool for investigating several biological, chemical and physical systems. Among the available detectors, SQUIDs are the most sensitive magnetic field and flux detectors and are rapidly approaching the quantum sensitivity limit. To reach such sensing capability, technological advances in the fabrication of nanoscale SQUIDs with submicrometric loops are needed. In this work we present a novel process for the fabrication of nanoscale SQUIDs, based on superconducting vertical Nb nanoconstrictions. The fabrication process uses laser lithogra- phy to define the device geometry, focused ion beam to mill the top surface of the Nb in a nanometer-sized region across the width of the film and anodization to define the final thickness of the nanoconstriction and at the same time to embed the ion- implanted amorphous layer produced by the FIB milling step. A preliminary electrical characterization of nano-sized single Josephson junctions and SQUIDs fabricated with this process is also reported.

This paper presents a software package for the automatic processing of bioclimatic data in the space and time domains whose final goal is to provide land and water management authorities with reliable information about the moisture/dryness level of a region and its water requirements. The current state of development of package is reported, presenting an example of application of the program to a specific case study.

A research study was conducted on a coastal irrigated agricultural area of southern Italy to assess the risks of aquifer degradation likely resulting from the intensive groundwater pumping from individual farm wells and reduced aquifer recharge. Information were collected both from farmers and delivery system's operators during a survey conducted in 2012 revealing that farmers depend mainly on groundwater with the aim to achieve flexible irrigation management as opposed to the rigid rotational delivery service of surface water supply provided by the local water management agency. The study area is intensively farmed by small land-holding growers with high-value micro-irrigated horticultural crops. Our team appraised the soil and aquifer degradation hazards using a simplified procedure for environmental risk assessment that allowed identifying the risk-generating processes, evaluating the magnitude of impacts, and estimating the overall risks significance. We also collected the stakeholders' perceptions on agricultural water management and use through field interviews, whereas parallel investigations revealed significant aquifer salinity increase during the recent years. As a final step, some preliminary risk mitigation options were appraised by exploring the growers' response to possible changes of irrigation deliveries by the water management agency. The present study integrated multi-annual observations, data interpretation, and modelling efforts, which jointly enabled the analysis of complex water management scenarios and the development of informed decisions.

In the last century, the International System of Units (SI) changed its perspectives, evolving from an artifact-based system to a system mainly based on physical processes at the atomic level and fundamental constants. In particular, the discovery of the Josephson effect made available a quantum voltage standard. As an consequence, in the last decade the worldwide consistency of the representation and maintenance of the electrical units and the electrical measurements based on it has improved a hundredfold. The Josephson effect, together with the quantum Hall effect for the definition of a modern resistance standard, will certainly play a major role in the next modernization of the SI, when the kilogram, the last base unit still based on a physical artifact, will be linked to fundamental constants. Furthermore, the definition of a new SI is strictly linked to the technological issues for the realisation of new devices capable to reproduce the electrical units with quantum accuracy. The challenges faced by modern metrology, sensing and quantum electronics are directing the new generations of devices towards smaller dimensions and higher levels of integration. Taking into account this requirement, at INRIM we fabricate and characterize superconducting quantum devices for a wide range of applications. The devices are based on the overdamped Nb/Al-AlOx/Nb SNIS (Superconductor-Normal metal-Insulator-Superconductor) Josephson junctions and exploiting thin film technology to guarantee a good control of electrical parameters of junctions, a higher reproducibility of their currentvoltage response, and increasingly an accurate dimension control. The main objective of the current experimental activity is addressed on downscaling the junction size from the micro to the nanoscale, exploiting three different lithographic techniques: optical lithography to realize SNISs with a size resolution of the order of the microme- ter, electron beam lithography (EBL) at the submicrometer range and, lastly, a recently proposed mesoscopic tunnel junction nano-fabrication technique, based on focused ion beam (FIB). We report the fabrication process and the electrical characterisation of a 1 Volt binary-divider array based on 8192 overdamped SNIS Josephson junctions for the programmable Josephson Voltage Standard (PJVS) [1] and of a 3D nano-SQUID (Super- conducting Quantum Interference Device) [2] as a sensor for the detection of magnetic nanoparticles. Preliminary results on Nb-based nano-constrictions fabricated by FIB and anodisation will also be presented [3]. The effect of FIB exposure and anodization voltage on the superconducting transition temperature and on the temperature dependence of the resistance of the nano-constrictions has been investigated, as well as the behaviour of these constrictions as overdamped SNS-like Josephson junctions. [1] V. Lacquaniti, N. De Leo, M. Fretto, A. Sosso, F. Mueller, J. Kohlmann, Superconductor Sci. Technol. 24 (2011). [2] C. Granata, A. Vettoliere, R. Russo, M. Fretto, N. De Leo, V. Lacquaniti, Appl. Phys. Lett. 103 (2013). [3] N. De Leo, M. Fretto, V. Lacquaniti, C. Cassiago, L. D'Ortenzi, L. Boarino, S. Maggi, accepted for publication in IEEE Trans. Appl. Supercond. (2016).

C27H36ClN2O9PS, monoclinic, C12/c1 (no. 15), a = 36.495(3) A?, b = 8.5574(4) A?, c = 20.487(4) A?, b = 101.18(2)°, V = 6276.8 A?3, Z = 8, Rgt(F) = 0.052, wRref(F2) = 0.125, T = 295 K.

NbCl(5)center dot(N,N '-dicyclohexylurea) 1a owns a distorted octahedral structure due to intramolecular NH center dot center dot center dot Cl bonding. The unit cell contains four units which are intermolecularly NH center dot center dot center dot Cl and NH center dot center dot center dot N bonded. An extended intramolecular network of H-bonding (N-H center dot center dot center dot Cl, CH center dot center dot center dot Cl, CH center dot center dot center dot N) causes the 3D self assembling of the units. Upon addition of base, the HCl release from 1a is observed with the transfer to Nb of the O-atom of the carbonylic function of the starting urea which is converted into the relevant carbodiimide CyN=C=NCy 4. The latter is quantitatively released by adding an excess of NEt(3) at 308 K (py and DBU are less efficient) with formation of the known NbOCl(3)(NEt(3))(2), isolated in quantitative yield. Increasing the temperature leads to a loss in selectivity as the formed DCC undergoes further reactions. At 350 K, the isocyanate CyN=C=O has been isolated in 60% yield besides a mixture of Nb-complexes. DFT calculations have been coupled to IR and NMR experiments for characterizing possible reaction intermediates and the behaviour of 1a. Several other MCl(x) species (ScCl(3), YCl(3), LaCl(3), TiCl(4), TaCl(5), AlCl(3), SnCl(4)) have been shown to be able to co-ordinate DCU but not all of them promote the conversion of urea into DCC.

Fourier syntheses providing electron density maps always show series-termination errors due to the limited experimental resolution. The worse the resolution, the worse the quality of the map: peaks are misplaced with respect to the true positions, positive and negative peaks occur, the peak profile is deformed. Two new algorithms have been developed aimed at reducing the resolution bias. The first one works in direct space [1,2], the second one in reciprocal space [3]. They are able to improve both peak positions and peak form in such a way that the map better fits the real atomic electron density. The new procedures have been introduced in EXPO2009, the strengthened and updated version of EXPO [4] and applied to the electron density maps provided by Direct Methods. Organic as well as metallorganic powder structures with non-atomic resolution experimental data have been tested. In spite of the difficulties in structure solution by powder data, the new approaches succeeded in several cases which could not be ,solved without the resolution bias correction. The theory of the resolution bias correction and its application by EXPO2009 will be presented.

Superconducting tunnel junctions (STJ) are promising high-resolution radiation detectors because of their larger energy resolution with respect to conventional Si-based detectors. We have developed a fabrication process for Nb/Al–AlO x /Nb STJ devices which produces junctions with subgap currents below 50 pA at 300 mK, a factor of 10 −6 less than the subgap current at 4.2 K. We report the details of the fabrication process and preliminary results on X-ray measurements at 300 mK with a 5 mC 55 Fe source.

We have developed a fabrication process for Nb-based STJ detectors which allows to fabricate junctions with subgap currents close to 20 pA at 300 mK, more than six orders of magnitude less than the subgap current at 4.2 K. The junctions are diamond-shaped devices, with areas between 20×20 and 100×100 µm2. We report the details of the fabrication process, together with an analysis of the grain structure of the films by AFM and XRD. We show the measured I - V curves at 300 mK and the temperature dependence of the subgap current between 300 and 1100 mK. We also report preliminary results on x-ray measurements at 300 mK with a 5 mC 55Fe source.

We will describe a system of three heterodyne receivers. Its mixers are based on SIS tunnel junctions which allow a very sensible downconversion of the detectable signal from 94 GHz, 225 GHz and 345 GHz to 1.5 GHz. This will allow the detection of molecular rotational transition lines from diffuse molecular clouds. The current status of a 94 GHz receiver, prototype of MASTER, will also be described. Technical design and cryogenic problems solution will be shown and we will focus our attention on the optical coupling technique based on Gaussian beam analysis

We have developed superconducting Nb/Al microstrip detectors. These devices appear to be very attractive due to their low sensitivity to radiation damage and aging, and to their high energy resolution. The samples are fabricated by superposing a 2 mm/spl times/2 mm Al area on a 5 /spl mu/m wide, 100 /spl mu/m long Nb strip. The thickness of each film is between 50 and 200 nm. We present the results of both steady and dynamical tests on Nb/Al bilayers, after irradiation with a /sup 241/Am alpha-source. We show that the performance of Nb/Al bilayers is better than that of single Nb strip devices.

A progress report of the MASTER project is presented here. MASTER is a system of three heterodyne receivers based on SIS (superconductor–insulator–superconductor) tunnel junction mixers. In our instrument these mixers will allow direct down-conversion from 94, 225, and 345 to 1.5 GHz, the IF where the signal will be detected. This instrument, coupled to a 2–4 m telescope like the one proposed for the DOME C base in Antarctica and in conjunction with an Acusto Optical Spectrometer, can be used to detect emission lines associated with molecular clouds in the interstellar medium. The current status of a 94 GHz receiver, the prototype of MASTER, will be presented too. The study of the optical coupling between the receiver and MITO telescope in the Italian Alps will also be described.

Preliminary results on the sensitivity to α-particles of Nb thin film microstrip detectors are presented.