A contribution to the mineralogy of the Larderello geothermal field. X-ray crystallographic studies on borate minerals "bechilite" and "lagonite" and crystal structure determination of ginorite

This work reports the results of mineralogical studies on some borate minerals from the Larderello geothermal field. XRD patterns of “bechilite” and “lagonite” confirmed they actually are respectively admixtures of sassolite and ammonioborite, and of sassolite with minor santite, gypsum and larderellite. Single crystal structural study of ginorite from the type locality, Sasso Pisano (Castelnuovo val di Cecina, Pisa) confirmed its isotypism with strontioginorite. Ginorite is monoclinic, space group P21/a, with unit cell parameters a =12.7673(1) Å, b = 14.3112(11), c = 12.7298(9), β= 101.055(5)° V=2282.8(2) Å3. The refinement of its crystal structure converged to R1 = 0.058 on the basis of 3387 reflections with Fo > 4σ (Fo). Analogously to strontioginorite, ginorite crystal structure can be described in terms of complex “sheets” parallel to (010), made up by borate groups and Ca coordination polyhedra, with interlayer linkage assured by Ca cations and hydrogen bonds. The cell volume contraction of ginorite respect to strontioginorite is related to the shrinkage of Ca coordination polyhedra present in the complex Me-borate sheets

Minimally Invasive Force Sensing for Tendon-driven Robots

Electronics engineerin

Chapter Minimally Invasive Force Sensing for Tendon-driven Robots

Electronics engineerin

XRF analysis of major and minor elements in silicate rocks using fused glass discs at high dilution ratio

XRF analysis of major and minor elements in silicate rocks using fused glass discs at high dilution ratio. X-ray fluorescence (XRF) is an accurate, rapid spectroscopic technique for chemical element determinations on rock samples. The aim of this research was to evaluate a calibration method for the determination of major and minor elements (Na, Mg, Al, Si, P, K, Ca, Ti, Mn, Fe) in silicate rocks using fused glass discs with a 1:30 sample/borate dilution. The analytical method has been calibrated by using forty-two international rock standards. The accuracy appears acceptable for many mineralogical and petrographic purposes. A high dilution ratio makes possible the use of a small amount of sample (225 mg) to obtain good castings in high-melting materials. By contrast, the decrease of the analytical intensity makes not easy the determination of trace elements at the typical concentration levels of geological samples

Misdiagnosed Chronic Pelvic Pain: Pudendal Neuralgia Responding to a Novel Use of Palmitoylethanolamide: Table 1

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Manipulation Planning and Control for Shelf Replenishment

Manipulation planning and control are relevant building blocks of a robotic system and their tight integration is a key factor to improve robot autonomy and allows robots to perform manipulation tasks of increasing complexity, such as those needed in the in-store logistics domain. Supermarkets contain a large variety of objects to be placed on the shelf layers with specific constraints, doing this with a robot is a challenge and requires a high dexterity. However, an integration of reactive grasping control and motion planning can allow robots to perform such tasks even with grippers with limited dexterity. The main contribution of the paper is a novel method for planning manipulation tasks to be executed using a reactive control layer that provides more control modalities, i.e., slipping avoidance and controlled sliding. Experiments with a new force/tactile sensor equipping the gripper of a mobile manipulator show that the approach allows the robot to successfully perform manipulation tasks unfeasible with a standard fixed grasp.Comment: 8 pages, 12 figures, accepted at RA

A Distributed Tactile Sensor for Intuitive Human-Robot Interfacing

Safety of human-robot physical interaction is enabled not only by suitable robot control strategies but also by suitable sensing technologies. For example, if distributed tactile sensors were available on the robot, they could be used not only to detect unintentional collisions, but also as human-machine interface by enabling a new mode of social interaction with the machine. Starting from their previous works, the authors developed a conformable distributed tactile sensor that can be easily conformed to the different parts of the robot body. Its ability to estimate contact force components and to provide a tactile map with an accurate spatial resolution enables the robot to handle both unintentional collisions in safe human-robot collaboration tasks and intentional touches where the sensor is used as human-machine interface. In this paper, the authors present the characterization of the proposed tactile sensor and they show how it can be also exploited to recognize haptic tactile gestures, by tailoring recognition algorithms, well known in the image processing field, to the case of tactile images. In particular, a set of haptic gestures has been defined to test three recognition algorithms on a group of 20 users. The paper demonstrates how the same sensor originally designed to manage unintentional collisions can be successfully used also as human-machine interface