Ulama Perempuan Dan Dedikasinya Dalam Pendidikan Islam (Telaah Pemikiran Rahmah El-yunusiyah)

Bahasa Indonesia:Istilah ulama biasanya identik dengan laki-laki, namun disini Rahmah El-Yunusiyah bisa disebut dengan ulama karena banyak hal yang melekat pada dirinya bisa merepresentasikan sebagai seorang alim yang mempunyai kapasitas keilmuan yang mumpuni tentang agama, sikap progresifnya untuk memperjuangkan kaumnya hingga pengakuan dari masyarakat luas baik di Indonesia hingga dunia Internasional terhadap kiprahnya dalam pembaharuan pendidikan bagi perempuan. Tulisan ini menelaah pemikiran Rahmah El-Yunusiyah tentang pendidikan perempuan dijamannya melalui penelusuran buku-buku teks sejarah dan berbagai literatur. Penulis berusaha menyajikan gambaran sejarah perjuangan pendidikan bagi perempuan yang telah dilakukan Rahmah El-Yunusiyah sebagai fakta sejarah tentang peran penting perempuan dalam bersosial masyarakat sehingga perlu untuk terus diperjuangkan hingga saat ini. Sebagaimana yang telah dilakukan Rahmah El-Yunusiyah sebagai pembaharu pendidikan bagi perempuan dengan mendirikan sekolah khusus perempuan dari jenjang sekolah dasar hingga perguruan tinggi. Kontribusinya dalam memperjuangkan pendidikan perempuan sangat besar, terlihat sekarang perempuan Indonesia telah dapat secara mudah untuk dapat mengakses pendidikan. Betapa perempuan sebagai tiang negara memiliki andil besar dalam menentukan masa depan bangsa. English:The term ulama is usually identical to men. However, Rahmah El-Yunusiyah is also called as an ulama because several factors attached to her such as representation as an alim with religious knowledge capacity, progressive attitudes for her community development, and the recognition of wider community both in Indonesia and in International regarding her work in woman education reform. This paper examines Rahmah El-Yunusiyah\u27s consideration about female education in the past through historical texts and related literatures. The author attempt to present a historical overview of El-Yunusiyah\u27s struggle for women\u27s education as the historical facts about the important role of women in society. El-Yunusiyah was as a reformer of woman education who set up woman school of the primary level up to the university level. Her great contribution in education is now visible that Indonesian women have easy access to education. This effort shows that women as a pillar of the state has a big responsibility to determine the future of the nation

Large Reverse Saturable Absorption at the Sunlight Power Level Using the Ultralong Lifetime of Triplet Excitons

Large reverse saturable absorption (RSA) at the sunlight power level was observed from a host–guest amorphous material composed of <i>d</i>₁₂-coronene as a guest and β-estradiol as a rigid amorphous host. The large highly symmetric two-dimensional (2D) aromatic structure of <i>d</i>₁₂-coronene doped into the rigid host causes ultralong triplet lifetime as well as high triplet yield, serving efficient accumulation of the triplet excitons of <i>d</i>₁₂-coronene under weak excitation light. The high absorption coefficient of the triplet state (σ₃₄) compared with that of the ground state (σ₀₁) for <i>d</i>₁₂-coronene is also caused by the highly symmetric 2D aromatic structure. The efficient accumulation of the triplet excitons and high σ₃₄ – σ₀₁ led to an onset of the RSA characteristics under irradiance below 10^–1 mW cm^–2. A film of the amorphous material showed a large decrease of transmittance from 66% at 0.02 mW cm^–2 to 24% at 50 mW cm^–2 for continuous light at 405 nm

Relaxation in Thin Polymer Films Mapped across the Film Thickness by Astigmatic Single-Molecule Imaging

We have studied relaxation processes in thin supported films of poly­(methyl acrylate) at the temperature corresponding to 13 K above the glass transition by monitoring the reorientation of single perylenediimide molecules doped into the films. The axial position of the dye molecules across the thickness of the film was determined with a resolution of 12 nm by analyzing astigmatic fluorescence images. The average relaxation times of the rotating molecules do not depend on the overall thickness of the film between 20 and 110 nm. The relaxation times also do not show any dependence on the axial position within the films for the film thickness between 70 and 110 nm. In addition to the rotating molecules we observed a fraction of spatially diffusing molecules and completely immobile molecules. These molecules indicate the presence of thin (<5 nm) high-mobility surface layer and low-mobility layer at the interface with the substrate

Bacteriochlorophyll Aggregates Self-Assembled on Functionalized Gold Nanorod Cores as Mimics of Photosynthetic Chlorosomal Antennae: A Single Molecule Study

We prepare artificial aggregates that mimic the structure and function of natural chlorosomal light harvesting complexes of green photosynthetic bacteria. Gold nanorods functionalized with hydroxyl groups and immobilized on a substrate serve as cores for the growth of bacteriochlorophyll (BChl) aggregates from a buffer solution. The BChl pigments form large self-assembled aggregate particles with sizes more than twice that of natural chlorosomes. The size is controllable by the aggregation time. The aggregates are characterized on a single-particle level by atomic force microscopy, electron microscopy, and single-molecule spectroscopy. The absorption and fluorescence spectral properties which reflect the molecular level arrangement of the BChl aggregates closely resemble those of the natural chlorosomes of the photosynthetic bacterium <i>Chlorobaculum tepidum</i>. On the other hand, the results of linear dichroism and circular dichroism are different from those of the chlorosomes and indicate a different mesoscopic structure for the artificial aggregates. These results emphasize the structural role played by the baseplate pigment–protein complex in natural chlorosomes

Mechanical Manipulation of Photophysical Properties of Single Conjugated Polymer Nanoparticles

Results on simultaneous atomic force microscopy (AFM) and fluorescence microspectroscopy on single nanoparticles of the conjugated polymer poly­[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) are presented. Single particle fluorescence spectra and defocused images confirm that the particles are composed of large numbers of randomly oriented conjugated segments (chromophores) with a wide distribution of the segment lengths. Mechanical contact of the particle surface with a sharp tip of the AFM probe causes reversible modification of the particle fluorescence intensity and spectra. The majority of the particles show an increase of fluorescence intensity and blue spectral shift upon contact with the tip. The fluorescence increase is correlated with the particle size and is most pronounced for the smallest particles. The phenomena are interpreted in terms of local disturbance of the MEH-PPV chain conformation by the probe tip

Position-Dependent Three-Dimensional Diffusion in Nematic Liquid Crystal Monitored by Single-Particle Fluorescence Localization and Tracking

Anisotropic mass diffusion in liquid crystals (LCs) is important from the point of both basic LC physics and their applications in optoelectronic devices. We use super-resolution fluorescence microscopy with astigmatic imaging to track 3D diffusion of quantum dots (QDs) in an ordered nematic LC. The method allowed us to evaluate the diffusion coefficients independently along the three spatial axes as well as to determine the absolute position of the QD with respect to the cell wall. We found variations of the diffusion coefficient along the different directions across the cell thickness and explained these as being due to changes of a tilt angle of the LC director. Close to the surface, the diffusion is slowed down due to the confinement effect of the cell wall. Overall, the QD diffusion is much slower than expected for a corresponding particle size. This phenomenon is suggested to originate from reorientation of the LC director in the vicinity of the particle

Intrachain Aggregates as the Origin of Green Emission in Polyfluorene Studied on Ensemble and Single-Chain Level

Polyfluorenes are conjugated polymers that show strong blue emission and as such have been explored for potential applications in light-emitting devices. However, heat treatment, prolonged exposure to air, or extended operation in electroluminescent devices can lead to an appearance of parasitic green emission that degrades the material performance. This phenomenon has been extensively studied over the past two decades, and two main and conflicting explanations, i.e., oxidation and formation of fluorenone species on the one hand and inter- or intrachain aggregation on the other, have been put forward. There is abundant experimental evidence to support either of these theories, and the question is far from settled. Here, we aim at getting deeper insight into the problem of the green emission origin using single-molecule spectroscopy performed on individual chains of poly­(9,9-di-<i>n</i>-octylfluorene) (PFO) to resolve the green emission band and reveal its spectral and temporal heterogeneity. We disperse single PFO chains in solid thin-film matrices of polystyrene (PS) and poly­(methyl methacrylate), as well as in solutions of cyclohexane, toluene, or PS/toluene, to simulate good and poor-solvent environments and environments with different permeabilities and diffusions of oxygen, to systematically study the effects of intrachain aggregation as well as oxidation on the appearance and characteristics of the green band. The studies are complemented by direct measurement of individual chain conformation by atomic force microscopy and by bulk measurements of photoluminescence (PL) lifetimes and quantum yield. The single-molecule results reveal two PL spectral forms in the region of the green emission, a vibrationally resolved type located around 500 nm and broad structureless type located toward lower energies, none of them sensitive to the presence of oxygen. These two types are characterized by different lifetimes of 1.4 and 5.1 ns, respectively, and their oscillator strengths are 2 orders of magnitude smaller compared to those of the blue emission band. These results point to two different optical transitions comprising the green band, and these have been assigned to the emission of H-aggregates and charge transfer or indirectly excited excimer states, respectively

Single-Molecule Study on Polymer Diffusion in a Melt State: Effect of Chain Topology

We report a new methodology for studying diffusion of individual polymer chains in a melt state, with special emphasis on the effect of chain topology. A perylene diimide fluorophore was incorporated into the linear and cyclic poly­(THF)­s, and real-time diffusion behavior of individual chains in a melt of linear poly­(THF) was measured by means of a single-molecule fluorescence imaging technique. The combination of mean squared displacement (MSD) and cumulative distribution function (CDF) analysis demonstrated the broad distribution of diffusion coefficient of both the linear and cyclic polymer chains in the melt state. This indicates the presence of spatiotemporal heterogeneity of the polymer diffusion which occurs at much larger time and length scales than those expected from the current polymer physics theory. We further demonstrated that the cyclic chains showed marginally slower diffusion in comparison with the linear counterparts, to suggest the effective suppression of the translocation through the threading-entanglement with the linear matrix chains. This coincides with the higher activation energy for the diffusion of the cyclic chains than of the linear chains. These results suggest that the single-molecule imaging technique provides a powerful tool to analyze complicated polymer dynamics and contributes to the molecular level understanding of the chain interaction

Single-Molecule Study on Polymer Diffusion in a Melt State: Effect of Chain Topology

We report a new methodology for studying diffusion of individual polymer chains in a melt state, with special emphasis on the effect of chain topology. A perylene diimide fluorophore was incorporated into the linear and cyclic poly­(THF)­s, and real-time diffusion behavior of individual chains in a melt of linear poly­(THF) was measured by means of a single-molecule fluorescence imaging technique. The combination of mean squared displacement (MSD) and cumulative distribution function (CDF) analysis demonstrated the broad distribution of diffusion coefficient of both the linear and cyclic polymer chains in the melt state. This indicates the presence of spatiotemporal heterogeneity of the polymer diffusion which occurs at much larger time and length scales than those expected from the current polymer physics theory. We further demonstrated that the cyclic chains showed marginally slower diffusion in comparison with the linear counterparts, to suggest the effective suppression of the translocation through the threading-entanglement with the linear matrix chains. This coincides with the higher activation energy for the diffusion of the cyclic chains than of the linear chains. These results suggest that the single-molecule imaging technique provides a powerful tool to analyze complicated polymer dynamics and contributes to the molecular level understanding of the chain interaction

Plasmon Enhancement of Triplet Exciton Diffusion Revealed by Nanoscale Imaging of Photochemical Fluorescence Upconversion

Photon upconversion based on the process of triplet–triplet annihilation in a system of organic donor and acceptor molecules has been attracting increasing attention because it can potentially lead to improved efficiency of light energy conversion devices working under sunlight irradiation. Here we aim to gain insight into the effect of localized plasmons of metal nanostructures on the individual photophysical steps involved in the upconversion mechanism. We present an optical microscopy study of the photophysical properties of plasmonic hybrid nanostructures composed of silver nanowires combined with an upconversion system consisting of platinum octaethylporphyrin donor molecules and 9,10-diphenylanthracene acceptor molecules dispersed in poly­(methyl methacrylate) thin film. Using an image-splitting technique, we simultaneously record upconversion and phosphorescence microscopy images and analyze the results to decouple the individual photophysical events. In addition to moderate intensity enhancement on the nanowires, the upconversion emission intensity can be enhanced up to 15-fold in the vicinity of hotspots formed by the silver nanowire junctions, compared with a 4–5-fold enhancement of phosphorescence in the same locations. Furthermore, whereas the phosphorescence enhancement is localized in the hotspots, the upconversion emission is enhanced along micrometer distances on the top of the nanowires. These findings are interpreted in terms of plasmon enhancement of Dexter-type energy transfer between the triplet states of the donor and acceptor as well as between the triplet states of the acceptor molecules. The latter gives rise to the apparent long-distance propagation of the triplet excitons along the nanowires