Stereolabile and Configurationally Stable Atropisomers of Hindered Aryl Carbinols.

CAN 143:132926 AN 2005:441860 CAPLUS (COPYRIGHT (C) 2008 ACS ON SCIFINDER (R)) ABSTRACT CARBINOLS OF THE AR-C(OH)R2 TYPE, AR BEING O-ISOPROPYLPHENYL, EXIST AS STEREOLABILE SYN-CLINAL (S.C.) AND ANTI-PERIPLANAR (AP) ATROPISOMERS WHEN R = ME, ET, I-PR. IN THE LATTER COMPD., THE MAJOR ATROPISOMER ALSO COMPRISES TWO ENANTIOMERIC FORMS THAT INTERCHANGE WITH A BARRIER OF 6.4 KCAL MOL-1. X-RAY DIFFRACTION, NOE EXPTS., AND AB INITIO CALCNS. INDICATE THAT THE S.C.-ATROPISOMER IS THE MORE STABLE FORM WHEN R = ME, I-PR, T-BU BUT IS THE LESS STABLE ONE WHEN R = ET. NMR SPECTRA AT VARIABLE TEMP. ALLOWED THE DETN. OF THE BARRIERS FOR THE INTERCONVERSION OF THE S.C.- INTO THE AP-ATROPISOMERS (ΔG.THERMOD. = 7.6, 8.8, AND 13.5 KCAL MOL-1 FOR ME, ET, I-PR, RESP.). WHEN R IS A TERT-BU GROUP, THE TWO ATROPISOMERS ARE CONFIGURATIONALLY STABLE: THE AP-ATROPISOMER IS OBTAINED AS THE KINETIC CONTROLLED COMPD., WHICH CAN BE TRANSFORMED INTO THE THERMODYNAMICALLY MORE STABLE S.C.-..

Structure, Conformation, and Stereodynamics of the Atropisomers of Highly Hindered Benzyl Ethers.

CAN 145:145171 AN 2006:476210 CAPLUS (COPYRIGHT (C) 2008 ACS ON SCIFINDER (R)) ABSTRACT LOW-TEMP. AND NOE NMR SPECTRA OF FOUR OF THE TITLE COMPDS. INDICATE THAT THEY ADOPT A SYNCLINAL (S.C.) CONFORMATION, IN AGREEMENT WITH THE PREDICTION OF AB INITIO COMPUTATIONS. IN THE CASE OF THE MOST-HINDERED DERIV. (COMPD. 4), THE CONFORMATION IS SYN-PERIPLANAR (SP), AS IS ALSO SHOWN BY X-RAY DIFFRACTION. SUCH STEREOLABILE SP- OR S.C.-ATROPISOMERS EXIST AS TWO CONFORMATIONAL ENANTIOMERS: THE CORRESPONDING ENANTIOMERIZATION BARRIERS, COVERING THE RANGE 6.6 TO 9.7 KCAL MOL-1, COULD BE MEASURED FOR ALL THE EXAMD. COMPDS. IN TWO CASES (COMPDS. 3 AND 5), THE MINOR ANTIPERIPLANAR (AP) ATROPISOMER HAS BEEN ALSO OBSD., AND THE S.C. TO AP INTERCONVERSION BARRIER MEASURED (11.7 AND 11.9 KCAL MOL-1, RESP.). IN ADDN., RESTRICTED ROTATION OF THE ISO-PR AND TERT-BU SUBSTITUENTS HAS BEEN DETECTED, AND THE CORRESPONDING BARRIERS HAVE BEEN DETD

Analisi carpologiche per la Vasca dello Specchio (Ferrara, XIV-XV sec. d.C.): metodologie d’indagine e risultati

Lo scavo condotto tra Corso Porta Reno e Via Vaspergolo, nel centro storico di Ferrara, ha portato alla luce un vano sotterraneo rettangolare denominato “Vasca dello Specchio”, utilizzato per lo smaltimento dei rifiuti tra XIV e XV secolo. Il riempimento, in parte già analizzato e pubblicato, è stato oggetto di nuove analisi carpologiche. I semi e i frutti, conservati prevalentemente per sommersione e in ottimo stato, sono complessivamente oltre 400.000 e la lista floristica comprende 168 taxa. La maggior parte dei reperti appartiene a piante coltivate/coltivabili o spontanee correlate all’uomo, che forniscono nuove informazioni sulla dieta vegetale e sull’ambiente urbano della Ferrara basso-medievale/rinascimentale. I reperti evidenziano anche pratiche domestiche e culinarie talora curiose

HIGH BAY CAPACITY UTILIZATION TOOL

Northrop Grumman’s Space Park facility has many inefficiencies in their high bay scheduling processes. Additionally, it is very hard for project managers to figure out the capabilities of each high bay in order to schedule their specific project. The purpose of this project is to develop a tool that can be used across the facility to easily create projects, assign projects, view room capabilities, and view a master schedule of the rooms. After researching commercially available tools, our approach to designing this system was to use tools that are already utilized at the facility (Microsoft Suite and Tableau) and engineer the system to do exactly what we need it to do for this facility. The design is a relational database managed in Microsoft Access that links to Tableau for a detailed schedule for all the rooms along with facility layouts on Microsoft Visio to show each facility at any time. These three programs are tied together with a user interface in Microsoft Access and available across the entire network at the Space Park facility via SharePoint. While our system would have higher initial cost to train employees on, it would save significant operating costs each year. If this system were to be installed and utilized into Northrop Grumman’s current operations, we estimate a cost savings between $10,000 and$25,000 over a ten year period. However, we ran into problems with the implementation of our tool due to having to use assumed data for our project. Although it is possible to expand this system, it is a lengthy process to add parameters for rooms and change the base layout of our design. Our largest recommendation for this system is that Northrop Grumman uses the base layout of our system (including the relational database design, user interface, and data visualization) to create a new system that has actual parameters of the room. This will yield the same results as installing the system that we have developed

Urban engineered slope collapsed in Rome on February 14th, 2018. Results from remote sensing monitoring

On February 14th, 2018, in the North-Western sector of the Municipality of Rome (Central Italy), in the framework of an excavation for building construction, a portion of a piling wall piling wall collapsed in an already densely urbanized area. Soil behind the collapsed piling wall slipped inside the excavation site dragging seven cars parked on one side of the road running parallel to the piling wall and affecting some residential buildings located on the opposite side of the road. Fortunately, no injuries were counted but the 22 families living in the buildings next to the damaged wall were evacuated. Following the piling wall collapse, the Civil Protection of Rome, thanks to the technical support of the Research Centre on Geological Risks (CERI) of the Sapienza University of Rome, started a continuous monitoring of the affected area through remote sensing techniques. In the first hours following the collapse, a Terrestrial Synthetic Aperture Radar Interferometer (TInSAR) and a terrestrial laser scanner (TLS) were installed with the aim to control the evolution of the process, to support the local authority to manage the associated residual risk, and to ensure the safety of workers during emergency operations. In this paper we discuss some of the results obtained by the monitoring of the involved area. Thanks to the comparisons between different surveys and the reconstruction of the pre-event geometries, the total volume involved in the failure was estimated around 850 m3. In addition, through the analysis of data acquired by the 18 multi-temporal TLS scans and the three and a half months of continuous TInSAR monitoring, the movement involving a portion of the filling material used for stabilization works was observed and described. Such movement, reaching a total displacement of about 270–300 mm, was monitored and reported in real time

Multisite PCET with photocharged carbon nitride in dark

A combination of photochemistry and proton coupled electron transfer (PCET) is a primary strategy employed by biochemical systems and synthetic chemistry to enable uphill reactions under mild conditions. Degenerate nanometer-sized n-type semiconductor nanoparticles (SCNPs) with the Fermi level above the bottom of the conduction band are strongly reducing and act more like metals than semiconductors. Application of the degenerate SCNPs is limited to few examples. Herein, we load microporous potassium poly(heptazine imide) (K-PHI) nanoparticles with electrons (e–) and charge balancing protons (H+) in an illumination phase using sacrificial agents. e–/H+ in the K-PHI nanoparticles are weakly bound and therefore could be used in a range of PCET reactions in dark, such as generation of aryl radicals from aryl halides, ketyl radicals from ketones, and 6e–/6H+ reduction of nitrobenzene to aniline. The integration of several features that until now were intrinsic for plants and natural photosynthesis into a transition metal free nanomaterial composed of abundant elements (C, N, and K) offers a powerful tool for synthetic organic chemistry

Spazio sicuro e non-sicuro: un'indagine sulle nuove strategie dell'abitare nel contesto della pandemia di COVID-19

The experience of Covid-19 gave us the need to rethink organisational methods of contemporary society, particularly public and domestic spaces. Our research used the pandemic struggle to examine current ways of looking at the safe and unsafe, entailing new practises of social action. This research was structured in two different stages. First we investigated a series of behaviours and perceptions within public and domestic spaces. Second we examined the strategies through which the subjects reorient the spaces and define new habitus and practices of dwelling. In both cases we focused on hygiene procedures and alternative measures undertaken to diminish the risk of contagion. The case studies are grouped by three different ranges of contagion in northern, central and southern Italy. They are discussed with reference to theoretical and methodological debates within social geography and cultural anthropology

High-momentum dynamic structure function of liquid 3He-4He mixtures: a microscopic approach

The high-momentum dynamic structure function of liquid 3He-4He mixtures has been studied introducing final state effects. Corrections to the impulse approximation have been included using a generalized Gersch-Rodriguez theory that properly takes into account the Fermi statistics of 3He atoms. The microscopic inputs, as the momentum distributions and the two-body density matrices, correspond to a variational (fermi)-hypernetted chain calculation. The agreement with experimental data obtained at $q=23.1$ \AA$^{-1}$ is not completely satisfactory, the comparison being difficult due to inconsistencies present in the scattering measurements. The significant differences between the experimental determinations of the 4He condensate fraction and the 3He kinetic energy, and the theoretical results, still remain unsolved.Comment: 18 pages, 11 figures, to appear in Phys. Rev.

Importance of the induced recharge term in riverbank filtration: Hydrodynamics, hydrochemical, and numerical modelling investigations

While ensuring adequate drinking water supply is increasingly being a worldwide challenging need, managed aquifer recharge (MAR) schemes may provide reliable solutions in order to guarantee safe and continuous supply of water. This is particularly true in riverbank filtration (RBF) schemes. Several studies aimed at addressing the treatment capabilities of such schemes, but induced aquifer recharge hydrodynamics from surface water bodies caused by pumping wells is seldom analysed and quantified. In this study, after presenting a detailed description of the Serchio River RBF site, we used a multidisciplinary approach entailing hydrodynamics, hydrochemical, and numerical modelling methods in order to evaluate the change in recharge from the Serchio river to the aquifer due to the building of the RBF infrastructures along the Serchio river (Lucca, Italy). In this way, we estimated the increase in aquifer recharge and the ratio of bank filtrate to ambient groundwater abstracted at such RBF scheme. Results highlight that in present conditions the main source of the RBF pumping wells is the Serchio River water and that the groundwater at the Sant’Alessio plain is mainly characterized by mixing between precipitation occurring in the higher part of the plain and the River water. Based on chemical mixing, a precautionary amount of abstracted Serchio River water is estimated to be on average 13.6 Mm3 /year, which is 85% of the total amount of water abstracted in a year (~16 Mm3). RBF is a worldwide recognized MAR technique for supplying good quality and reliable amount of water. As in several cases and countries the induced recharge component is not duly acknowledged, the authors suggest including the term “induced” in the definition of this type of MAR technique (to become then IRBF). Thus, clear reference may be made to the fact that the bank filtration is not completely due to natural recharge, as in many cases of surface water/groundwater interactions, but it may be partly/almost all human-made

The Effect of the Short-Range Correlations on the Generalized Momentum Distribution in Finite Nuclei

The effect of dynamical short-range correlations on the generalized momentum distribution $n(\vec{p},\vec{Q})$ in the case of $Z=N$, $\ell$-closed shell nuclei is investigated by introducing Jastrow-type correlations in the harmonic-oscillator model. First, a low order approximation is considered and applied to the nucleus $^4$He. Compact analytical expressions are derived and numerical results are presented and the effect of center-of-mass corrections is estimated. Next, an approximation is proposed for $n(\vec{p}, \vec{Q})$ of heavier nuclei, that uses the above correlated $n(\vec{p},\vec{Q})$ of $^4$He. Results are presented for the nucleus $^{16}$O. It is found that the effect of short-range correlations is significant for rather large values of the momenta $p$ and/or $Q$ and should be included, along with center of mass corrections for light nuclei, in a reliable evaluation of $n(\vec{p},\vec{Q})$ in the whole domain of $p$ and $Q$.Comment: 29 pages, 8 figures. Further results, figures and discussion for the CM corrections are added. Accepted by Journal of Physics