193,615 research outputs found
The heats of formation of the haloacetylenes XCCY [X, Y = H, F, Cl]: basis set limit ab initio results and thermochemical analysis
The heats of formation of haloacetylenes are evaluated using the recent W1
and W2 ab initio computational thermochemistry methods. These calculations
involve CCSD and CCSD(T) coupled cluster methods, basis sets of up to spdfgh
quality, extrapolations to the one-particle basis set limit, and contributions
of inner-shell correlation, scalar relativistic effects, and (where relevant)
first-order spin-orbit coupling. The heats of formation determined using W2
theory are: \hof(HCCH) = 54.48 kcal/mol, \hof(HCCF) = 25.15 kcal/mol,
\hof(FCCF) = 1.38 kcal/mol, \hof(HCCCl) = 54.83 kcal/mol, \hof(ClCCCl) = 56.21
kcal/mol, and \hof(FCCCl) = 28.47 kcal/mol. Enthalpies of hydrogenation and
destabilization energies relative to acetylene were obtained at the W1 level of
theory. So doing we find the following destabilization order for acetylenes:
FCCF ClCCF HCCF ClCCCl HCCCl HCCH. By a combination of W1
theory and isodesmic reactions, we show that the generally accepted heat of
formation of 1,2-dichloroethane should be revised to -31.80.6 kcal/mol, in
excellent agreement with a very recent critically evaluated review. The
performance of compound thermochemistry schemes such as G2, G3, G3X and CBS-QB3
theories has been analyzed.Comment: Mol. Phys., in press (E. R. Davidson issue
A New Athenian Gymnasium from the 4th Century BC?
Schriftquellen belegen, dass das Gymnasium der Athener Akademie vom 6. Jh. v. Chr. bis mindestens zum 2. Jh. n. Chr. benutzt wurde. Der Ort wurde anhand von Texten und einem Horosstein lokalisiert und seit 1929 mehrfach untersucht. Zu den freigelegten Strukturen gehören im Süden ein rechteckiger Bau mit Hof, der als Palaestra der Akademie gedeutet wurde, und im Norden ein großer quadratischer Peristylbau, der wenig beachtet wurde. Dieser Beitrag revidiert die Identifizierung der beiden Bauten. Es wird gezeigt, dass der Hof des südlichen Baus in die Spätantike gehört und nicht als Palaestra fungiert haben kann. Stattdessen ist der quadratische Bau, dessen Peristyl von Räumen umgeben und der ins 4. Jh. v. Chr. zu datieren ist, anhand von Plan und Inschriften als Palaestra zu identifizieren
Reply to Comment on 'Critical behaviour in the relaminarization of localized turbulence in pipe flow'
This is a Reply to Comment arXiv:0707.2642 by Hof et al. on Letter
arXiv:physics/0608292 which was subsequently published in Phys Rev Lett, 98,
014501 (2007).
In our letter it was reported that in pipe flow the median time for
relaminarisation of localised turbulent disturbances closely follows the
scaling . This conclusion was based on data from
collections of 40 to 60 independent simulations at each of six different
Reynolds numbers, Re. In the Comment, Hof et al. estimate differently
for the point at lowest Re. Although this point is the most uncertain, it forms
the basis for their assertion that the data might then fit an exponential
scaling , for some constant A, supporting Hof et al.
(2006) Nature, 443, 59. The most certain point (at largest Re) does not fit
their conclusion and is rejected. We clarify why their argument for rejecting
this point is flawed. The median is estimated from the distribution of
observations, and it is shown that the correct part of the distribution is
used. The data is sufficiently well determined to show that the exponential
scaling cannot be fit to the data over this range of Re, whereas the fit is excellent, indicating critical behaviour and supporting
experiments by Peixinho & Mullin 2006.Comment: 1 page, 1 figur
Hubungan antara Realisasi Dana Bantuan Operasional Kesehatan dengan Indikator Gizi Kia di Kabupaten/kota Provinsi Jawa Tengah Tahun 2012
Background: Health Operational Fund (HOF) is a grant fromcentral government through the Ministry of Health. The goal isto help local governments for implementing health servicesbased on Minimum Service Standards (MSS) in the field ofhealth to accelerate the achievement of the MillenniumDevelopment Goals (MDGs). Health development policies in2010-2014 are directed to enable availability of fundamemntalhelalth access that cheap and affordable especially for thelower-middle gorups. This is indicated by increasing lifeexpectancy, infant mortality and maternal mortality. One of thehealth priority programs is Nutrition Program and the Maternaland Child Health (MCH).Methods: This research is quantitative research. Analysismethod uses a simple regression. Research data are secondarydata in 2012 of 35 districts/cities in Central Java Province.Results: The realization of Health Operational Fund (HOF) issignificant ( Sig.0,000 < ±=1%) on neonatus first visit/KN1, therealization of Health Operational Fund (HOF) is significant (Sig.0,000 < ±=1%) on assistance by skilled health personnel/Pn, and the realization of Health Operational Fund (HOF) issignificant ( Sig.0,000 < ±=1%) on children weighing or D/S.Coefficient of determination (r ²) is 0.629 for the effect of HOFon KN1, 0.636 for the effect of HOF on Pn, and 0.690 for HOFon D/S. The result of classical assumptions shows that residualvariables are normally distributed, despite heteroscedasticityand despite autoccorelation.Conclusion: HOF has positive effect and significant on KN1,HOF has positive effect and significant on Pn, and HOF haspositive effect and significant on D/SKey Words: HOF, MCH Nutrition, Simple Regression, CentralJav
Towards Enhanced Usability of IT Security Mechanisms - How to Design Usable IT Security Mechanisms Using the Example of Email Encryption
Nowadays, advanced security mechanisms exist to protect data, systems, and
networks. Most of these mechanisms are effective, and security experts can
handle them to achieve a sufficient level of security for any given system.
However, most of these systems have not been designed with focus on good
usability for the average end user. Today, the average end user often struggles
with understanding and using security mecha-nisms. Other security mechanisms
are simply annoying for end users. As the overall security of any system is
only as strong as the weakest link in this system, bad usability of IT security
mechanisms may result in operating errors, resulting in inse-cure systems.
Buying decisions of end users may be affected by the usability of security
mechanisms. Hence, software provid-ers may decide to better have no security
mechanism then one with a bad usability. Usability of IT security mechanisms is
one of the most underestimated properties of applications and sys-tems. Even IT
security itself is often only an afterthought. Hence, usability of security
mechanisms is often the after-thought of an afterthought. This paper presents
some guide-lines that should help software developers to improve end user
usability of security-related mechanisms, and analyzes com-mon applications
based on these guidelines. Based on these guidelines, the usability of email
encryption is analyzed and an email encryption solution with increased
usability is presented. The approach is based on an automated key and trust
man-agement. The compliance of the proposed email encryption solution with the
presented guidelines for usable security mechanisms is evaluated
Останні роки життя Володимира Винниченка
Door het negatief advies van het Hof van Justitie blijft er een accountability-vacuüm waarbij de GBVB gestelde EU-handelingen noch door het Hof van Justitie noch door het EVRM kunnen worden getoetst op mensenrechtenschending. De toetreding van de EU tot het EVRM zou het mogelijk maken de rechtsmacht over de GBVB-handelingen uit te breiden doordat het ontwerp-toetredingsakkoord voorziet in een co-respondentmechanisme en een procedure van voorafgaande beoordeling door het Hof van Justitie. Door het negatief advies blijft het Hof van Justitie lijdzaam toezien hoe GBVB-handelingen enkel kunnen worden aangevochten in een EHRM-procedure tegen de lidstaat
Miniaturen aus Handschriften der Kgl. Hof- und Staatsbibliothek in München
MINIATUREN AUS HANDSCHRIFTEN DER KGL. HOF- UND STAATSBIBLIOTHEK IN MÜNCHEN
Miniaturen aus Handschriften der Kgl. Hof- und Staatsbibliothek in München ([86]
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