Chemical Reasoning Based on an Invariance Property: Bond and Lone Pair Pictures in Quantum Structural Formulas

Chemists use one set of orbitals when comparing to a structural formula, hybridized AOs or NBOs for example, and another for reasoning in terms of frontier orbitals, MOs usually. Chemical arguments can frequently be made in terms of energy and/or electron density without the consideration of orbitals at all. All orbital representations, orthogonal or not, within a given function space are related by linear transformation. Chemical arguments based on orbitals are really energy or electron density arguments; orbitals are linked to these observables through the use of operators. The Valency Interaction Formula, VIF, offers a system of chemical reasoning based on the invariance of observables from one orbital representation to another. VIF pictures have been defined as one-electron density and Hamiltonian operators. These pictures are classified in a chemically meaningful way by use of linear transformations applied to them in the form of two pictorial rules and the invariance of the number of doubly, singly, and unoccupied orbitals or bonding, nonbonding, and antibonding orbitals under these transformations. The compatibility of the VIF method with the bond pair – lone pair language of Lewis is demonstrated. Different electron lone pair representations are related by the pictorial rules and have stability understood in terms of Walsh’s rules. Symmetries of conjugated ring systems are related to their electronic state by simple mathematical formulas. Description of lone pairs in conjugated systems is based on the strength and sign of orbital interactions around the ring. Simple models for bonding in copper clusters are tested, and the bonding of O2 to Fe(II) in hemoglobin is described. Arguments made are supported by HF, B3LYP, and MP2 computations

Mining topological relations from the web

Topological relations between geographic regions are of interest in many applications. When the exact boundaries of regions are not available, such relations can be established by analysing natural language information from web documents. In particular we demonstrate how redundancy-based techniques can be used to acquire containment and adjacency relations, and how fuzzy spatial reasoning can be employed to maintain the consistency of the resulting knowledge base

Kajian Persepsi Dan Partisipasi Masyarakat Terhadap Program Kebun Bibit Rakyat (Kbr) Di Desa Bulusulur Kabupaten Wonogiri

Program Kebun Bibit Rakyat (KBR) merupakan salah satu program Rehabilitasi Hutan dan Lahan (RHL) yang berbasis swakelola kelompok masyarakat dan bertujuan untuk menyediakan bibit berkualitas baik sehingga diharapkan dapat meningkatkan minat tanam masyarakat. Salah satu desa yangmenerima bantuan pada tahun 2012 adalah Desa Bulusulur, Kabupaten Wonogiri. Persepsi terhadap program KBR yang meliputi pemahaman, motivasi, kepuasaan dan keuntungan serta manfaat yang diperoleh dinilai positif, hal ini terlihat daritingginya antusiasme masyarakat serta kepuasaan yang dirasakan masyarakat terhadap pelaksanaan program. Selaras dengan hal tersebut, partisipasi yang meliputi peran, bantuk, potensi partisipasi serta review pelaksanaan program juga terlaksana dengan baik dan sesuai dengan peraturan yang menaungi. Panitia dan masyarakat memiliki peran dan bentuk partisipasi yang hampir sama. Hanya pada tahap rencana dan rancangan dan dalam bentuk ide dan gagasan tidak ada pelibatan masyarakat umum di dalamnya

Kajian Dampak Erupsi Merapi terhadap Perubahan Penghidupan Masyarakat Tani Desa Ngargomulyo untuk Pengembangan Konsep Sister Village dalam Manajemen Bencana

Bencana erupsi Gunung Merapi yang terjadi pada tahun 2010 menyebabkan dampak baik secara fisik maupun tata sosial ekonomi masyarakat Desa Ngargomulyo. Adanya Perubahan aktivitas pasca bencana menjadi perangsang masyarakat lokal untuk melakukan recovery secara mandiri dan sebagai strategi masyarakat untuk meningkatkan penghidupan mereka menjadi lebih baik. Penelitian ini bertujuan untuk (1) Mengidentifikasi dampak bencana erupsi Merapi tahun 2010 terhadap Perubahan penghidupan masyarakat tani Desa Ngargomulyo; (2) Mengidentifikasi strategi bertahan hidup masyarakat tani Desa Ngargomulyo pasca erupsi Merapi tahun 2010; (3) Mengidentifikasi persepsi masyarakat Desa Ngargomulyo terkait dengan pengembangan konsep Sister Village dalam manajemen bencana. Penelitian ini dilakukan dengan teknik pengambilan sampel yaitu simple random sampling. Sedangkan teknik analisis yang digunakan adalah analisis deskriptif kualitatif yang mendeskripsikan mengenai obyek penelitian berdasarkan data dan variabel yang diperoleh dari responden yang telah ditentukan sesuai dengan tujuan penelitian. Hasil penelitian menunjukkan bahwa bencana erupsi Merapi tahun 2010 memberikan pengaruh terhadap Perubahan kondisi aset, akses dan aktivitas. Strategi pemulihan penghidupan masyarakat sangat bergantung pada kapabilitas yang mereka miliki diantaranya kepemilikan aset, akses dan aktivitas. Sedangkan pengembangan konsep Sister Village sebagai konsep manajemen bencana yang baru masih dalam tahap penyempurnaan dan diharapkan dapat menjadi solusi tepat dalam penanganan bencana di Indonesi

Unspecified Verticality of Franck-Condon Transitions, Absorption and Emission Spectra of Cyanine Dyes, and a Classically Inspired Approximation

The computed vertical energy, Ev,a/f, from the equilibrium geometry of the initial electronic state is frequently considered as representative of the experimental excitation/emission energy, Eabs/fl = hc/λmax. Application of the quantum mechanical version of the Franck–Condon principle does not involve precise specification of nuclear positions before, after, or during an electronic transition. Moreover, the duration of an electronic transition is not experimentally accessible in spectra with resolved vibrational structure. It is shown that computed vibronic spectra based on TDDFT methods and application of quantum mechanical FC analysis predict Eabs = hc/λmax with a 10-fold improvement in accuracy compared to Ev,a for nine cyanine dyes. It is argued that part of the reason for accuracy when this FC analysis is compared to experiment as opposed to Ev,a/f is the unspecified verticality of transitions in the context of the quantum version of the FC principle. Classical FC transitions that preserve nuclear kinetic energy before and after an electronic transition were previously found to occur at a weighted average of final and initial electronic state molecular geometries known as the r-centroid. Inspired by this approach a qualitative method using computed vertical and adiabatic energies and the harmonic approximation is developed and applied yielding a 5-fold improvement in accuracy compared to Ev,a. This improvement results from the dominance of low frequency vibronic transitions in the cyanine dye major band. The model gives insight into the nature of the redshift when qPCR dye EvaGreen is complexed to λDNA and is applicable to the low frequency band of similar non cyanine dyes such as curcumin. It is found that the computed vibronic cyanine dye spectra from time-dependent FC analysis at 0 K and 298 K show decreased intensity at higher temperature suggestive of increased intensity with restricted motion shown when cyanine dyes are used in biomedical imaging. A 2-layer ONIOM model of the DNA minor groove indicates restricted motion of the TC-1 dye excited state in this setting indicative of enhanced fluorescence

Quantum Chemical Lipophilicities of Antimalarial Drugs in Relation to Terminal Half-Life

According to the WHO, artemisinin-based combination therapies (ACTs) have been integral to the recent reduction in deaths due to Plasmodium falciparum malaria. ACT-resistant strains are an emerging problem and have evolved altered developmental stages, reducing exposure of the most susceptible stages to artemisinin drugs in popular ACTs. Lipophilicity, log Kow, is a guide in understanding and predicting pharmacokinetic properties such as terminal half-life which alters drug exposure. Consistent log Kow values are not necessarily available for artemisinin derivatives designed to extend terminal half-life, increase bioavailability, and reduce neurotoxicity. For other drugs used in ACTs, an assortment of experimental and computational log Kow values are available in the literature and in some cases, do not account for subtle but important differences between closely related structures such as between diastereomers. Quantum chemical methods such as density functional theory (DFT) used with an implicit solvent model allow for consistent comparison of physical properties including log Kow and distinguish between closely related structures. To this end, DFT, B3LYP/6-31G(d), with an implicit solvent model (SMD) was used to compute ΔGowo and ΔGvowo for 1-octanol–water and olive oil–water partitions, respectively, for 21 antimalarial drugs: 12 artemisinin-based, 4 4-aminoquinolines and structurally similar pyronaridine, and 4 amino alcohols. The computed ΔGowo was close to ΔGowo calculated from experimental log Kow values from the literature where available, with a mean signed error of 2.3 kJ/mol and mean unsigned error of 3.7 kJ/mol. The results allow assignment of log Kow for α-and β-diastereomers of arteether, and prediction of log Kow for β-DHA and five experimental drugs. Linear least square analysis of log Kow and log Kvow versus terminal elimination half-life showed strong linear relationships, once the data points for the 4-aminoquinoline drugs, mefloquine and pyronaridine were found to follow their own linear relationship, which is consistent with their different plasma protein binding. The linear relationship between the computed log Kvow and terminal elimination half-life was particularly strong, R2 = 0.99 and F = 467, and can be interpreted in terms of a simple pharmacokinetic model. Terminal elimination half-life for β-DHA and four experimental artemisinin drugs were estimated based on this linear relationship between log Kvow and terminal t1/2. The computed log Kow and log Kvow values for epimers α- and β-DHA and α and β-arteether provide physical data that may be helpful in understanding their different pharmacokinetics and activity based on their different molecular geometries. Relative solubility of quinine and quinidine are found to be sensitive to thermal corrections to enthalpy and to vibrational entropy and do not follow the general trend of longer terminal t1/2 with greater predicted log Kow. Geometric relaxation of α- and β-DHA in solvent and inclusion of thermal correction for enthalpy and entropy results in correct prediction that α-DHA is favored in aqueous environments compared to β-DHA. Predictions made regarding experimental drugs have implications regarding their potential use in response to artemisinin drug-resistant strains

Pengolahan Limbah Cair Tahu Menggunakan Membran Nanofiltrasi Silika Aliran Cross Flow Untuk Menurunakan Kadar Nitrat Dan Amonium

Industri tahu di Indoesia saat ini telah berkembang pesat sehingga menyebabkan peningkatan jumlah limbah tahu.Limbah cair tahu yang dihasilkan langsung dibuang ke badan air, hal ini mengakibatkan menurunnya kualitas badan air tersebut. Penggunaan pasir silika sebagai bahan baku pembuatan membran nanofiltrasi menjadi alternatif dalam mengolah limbah cair tahu untuk menurunkan kadar nitrat dan amonium. Sintesis silika dilakukan dengan metode alkalifusion yaitu pembakaran pasir silika dengan suhu 360°C. Untuk pembuatan membran digunakan variasi membran yaitu 5;8;10 gram, serta variasi perbandingan volume antara air limbah dengan air PDAM yaitu 1:1 ; 1:2 ; 1:3. Dengan tujuan untuk mengetahui massa silika optimum, nilai koefisien rejeksi dan nilai fluks yang paling baik. Membran nanofiltrasi yang dihasilkan akan diujikan pada reaktor aliran cross flow untuk mencegah terjadinya fouling dini. Pada penelitian ini didapatkan massa silika yang paling optimum untuk pembuatan membran adalah membran dengan massa silika 5 gram. Nilai koefisien rejeksi yang paling baik adalah 92,17% dengan variasi membran 5 gram dan volume air limbah 100%. Sedangkan nilai fluks yang paling baik adalah 3,67 L/m2.jam dengan variasi membran 8 gram dan volume air limbah 25%

Perancangan dan Analisis Antena Dipole pada Frekuensi 2,4 GHz untuk Modul Xbee S2 Pro Menggunakan HFFS 14.0

Xbee s2 pro module works at 2,4 Ghz using IEEE 802.15.4 standard and polarization are linear. There are many types of antennas that can be used, which one is the dipole antenna. The simulation model implemented in this study uses Ansoft HFSS 14.0 software. HFSS stands for high frequency structure simulator is a pioneer in the use of finite element method for electromagnetic wave simulators that implement tangential vector finite elements, adaptive meshing and Adaptive Lanczos-Pade Sweep (ALPS) technology. By using HFSS 14.0 simulation, the axial ratio value of 35.0359 dB that means linier polarization. For the value of s-parameter -21,1851 db and VSWR value approaches 1, that is 1.5195 db. The gain value obtained is 0.7469 dB, the gain value needs to be optimized by using a metamaterial to get a good gain