1,243 research outputs found
Tuning the electronic, photophysical and charge transfer properties of small D-A molecules based on Thienopyrazine-terthienyls by changing the donor fragment: A DFT study
Indexación: Scopus.Four acceptor-donor organic conjugated molecules based on thieno[3,4-b]pyrazine-terthienyls were analyzed in order to explore the effect of the donor substituent on their molecular structures, electronic and optical properties. Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD/DFT) calculations were carried out employing the B3LYP hybrid functional in combination with the 6-31G(d,p) basis set. The results suggests that the addition of electron-donating substituents to the conjugated molecules can diminish their energy gap value, which is beneficial to the photon harvesting. The lowest-lying absorption spectra of compounds substituted with electron donor groups exhibited a red-shift and a high oscillation factor compared with the unsubstituted molecule. Additionally, the ionization potential (IP), electron affinity (EA), reorganization energy (λ) and open-circuit voltage (Voc) of the molecules were evaluated. According to these values, the molecules show good photovoltaic properties, and efficient charge transfer for hole and electron and balanced charges.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0717-97072017000303637&lng=en&nrm=iso&tlng=e
Analisis Permintaan Jasa Angkutan Penumpang Udara Di Bandara Sultan Syarif Kasim II Pekanbaru
This research conducted in Sultan SyarifKasim II Airport in Pekanbaru, the capital city of Riau. The purpose of this research was to determine what factors affect the demand for air transport services on domestic flights and International flights. Data analysis method used in this research is multiple linear regression with statistical test. The results of research on domestic flights for sample F show that GDP per capita for ticket prices of the airline Garuda Indonesia and Lion Air was simultaneously affect the demand for air transport services. Based on sample t is concluded that the GDP per capita for ticket prices of the airline Garuda Indonesia is partially affected and the ticket prices of the airline Lion Air does not partially affect the demand for air transport services on domestic flights. The coefficient of multiple determination for Garuda Indonesia is 0.989, and the coefficient of multiple determination for Lion Air is 0,986. The results of research on International flights for sample F show that the exchange rate and prices simultaneously affect the demand for air transport services. Based on sample t is concluded that the exchange rate and prices is partially affected the demand for air transport services on International flights.The coefficient of multiple determination for Express Air is 0,850
Penerapan Model Pembelajaran Aktif Inquiring Minds Want to Know Guna Meningkatkan Prestasi Belajar Akuntansi Pad Siswa Kelas X Akuntansi Smk Murni 2 Surakarta Tahun Ajaran 2012/2013
The objective of research was to find out whether or not there is an improvement of Accounting learning achievement through inquiring minds want to know type of active learning model in the X Accounting graders of SMK Murni 2 Surakarta in the school year of 2012/2013. This study employed a Classroom Action Research (CAR). The subject of research was the X Accounting graders of SMK Murni 2 Surakarta consisting of 21 students. The result of research showed the increased percentage of affective, psychomotor, and cognitive ability levels among the students. The mean percentage affective level was 69.29% in cycle I and 78.10% in cycle II, increasing by 8.81%. The mean percentage of psychomotor ability was 70.24% in cycle I and 77.38% in cycle II, increasing by 7.14%. The mean percentage of cognitive ability was 69.42% in cycle I and 77.90% in cycle II, increasing by 8.48%. Considering the research conducted, it could be concluded that the inquiring minds want to know type of active learning model use could improve the accounting learning achievement (either process or product). It was reflected on several indicators of student ability assessment improving in each cycle
Performance Improvement of the Parabolic Trough Solar Collector Using Different Types of Fluids with Numerical Simulation
المركزات الشمسية وسيلة مهمة لأستخدام طاقة الشمس. هنالك عدة انواع من المركزات الشمسية. في العمل الحالي محاولة تجريبية لتحسين الاداء الحراري للجامع الشمسي ذو القطع المكافىء بأستخدام ثلاثة موائع مختلفة (ماء، ماء مقطر مع جزيئات اوكسيد النحاس النانوية، ماء مقطر مع جزيئات الالومينا النانوية) مع نسبة تركيز 0.01 %، وسرعة جريان 20 لتر/ساعة، وبدون استخدام نظام التتبع مع محاكاة رقمية. الاختبار التجريبي تم في مدينة بغداد في قسم الهندسة الكهروميكانيكية في الجامعة التكنولوجية خلال ايام شهر تشرين الاول 2017 خلال وقت النهار (9 صباحا - 15 مساءا). النتائج المحسوبة للموائع الثلاثة كما يلي:
- استخدام (CuO + ماء مقطر) يزيد معدل درجات الحرارة الخارجة بنسبة 10.4% ومعدل المكاسب الحرارية زاد بنسبة 11% ومعدل الكفاءات زاد بنسبة 15.5%.
- استخدام ( + ماء مقطر ) يزيد معدل درجات الحرارة الخارجة بنسبة 4% ومعدل المكاسب الحرارية زاد بنسبة 6.5 % ومعدل الكفاءات زاد بنسبة 8.2%.
هذه النتائج تبين ذلك، استخدام المائع (ماء مقطر + CuO) يعطي أفضل اداء بالمقارنة مع المائعين الاخرين المستخدمين في هذا العمل.Solar concentrators are an important facility to utilize the solar energy. There are many kinds of solar concentrators. In this work an experimental has been implemented to improve the thermal performance of Parabolic Trough Solar Collector (PTSC) using three different fluids as a working fluid (water, nanoparticles of CuO mixed with distilled water nanoparticles of mixed with distilled water) with concentration ratio 0.01% and mass flow rate 20Lt/hr without tracking system. The experimental tests have been carried out in electro-mechanical engineering department at university of technology in Baghdad city during October 2017 and daytime between (9am -15pm) hours. The obtained results for three different fluids are as follows:
- Using (CuO + distilled water) as a working fluid increases the average of the output temperatures by 10.4%, the average of useful heat gains increases by 11% and the average of the collector efficiencies increases by15%.
- Using ( +distilled water) as a working fluid increased the average of output temperatures by 4%, the average of useful heat gains is increased by 6.5% and the average of collector efficiencies is increased by 8.2%.  
Examining the cancellation mechanism of neutron EDM in a model with dilaton-dominated susy breaking
We examine the cancellation mechanism between the different contributions to
the electric dipole moment of the neutron in a model with dilaton-dominated
SUSY breaking. We find these accidental cancellations occur at few points in
parameter space. For a wide region of this space we must constrain the phase of
to be of order and have the phases of and strongly
correlated in order to have small neutron EDM. Moreover, we consider the
indirect CP violation parameter in this region where the electric
dipole moment is less than the experimental limit and find that we can generate
of order
The Hilbert basis method for D-flat directions and the superpotential
We discuss, using the Hilbert basis method, how to efficiently construct a
complete basis for D-flat directions in supersymmetric Abelian and non-Abelian
gauge theories. We extend the method to discrete (R and non-R) symmetries. This
facilitates the construction of a basis of all superpotential terms in a theory
with given symmetries.Comment: 11 pages; a related mathematica code can be found at
http://einrichtungen.ph.tum.de/T30e/codes/NonAbelianHilbert
Higgsino mass matrix ansatz for MSSM
An ansatz, Det. for the Higgsino mass matrix in string
orbifold trinification is suggested toward the minimal supersymmetric standard
model(MSSM). Small instanton solutions effective around the GUT scale can
fulfil this condition. An argument that the couplings contain a moduli field is
given for a dynamical realization of this Higgsino mass matrix ansatz.Comment: 15 pages of LaTeX fil
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