NMR study of a bimesogenic liquid crystal with two nematic phases

Recent interest in bimesogenic liquid crystals showing two nematic phases has led us to investigate the nematic mean-field interactions in these nematic phases by using rigid solutes as probes. The nematic potential that is modelled by two independent Maier-Saupe terms is successful in fitting the observed dipolar couplings (order parameters) of para-, meta- and ortho-dichlorobenzene solutes in both the nematic phases of 39 wt% of 4-n-pentyl-4′-cyanobiphenyl (5CB) in α,ω-bis(4-4′-cyanobiphenyl)nonane (CB_C9_CB) to better than the 5% level. The derived liquid-crystal potential parameters G₁ and G₂ for each solute in the N and Ntb phases will be discussed. The most interesting observation is that G1 (associated with size and shape interactions) is almost constant in the Ntb phase, whereas G₂ (associated with longer-range electrostatic interactions) has large variation, even changing sign

Anomalous increase in nematic-isotropic transition temperature in dimer molecules induced by magnetic field

We have determined the nematic-isotropic transition temperature as a function of applied magnetic field in three different thermotropic liquid crystalline dimers. These molecules are comprised of two rigid calamitic moieties joined end to end by flexible spacers with odd numbers of methylene groups. They show an unprecedented magnetic field enhancement of nematic order in that the transition temperature is increased by up to 15K when subjected to 22T magnetic field. The increase is conjectured to be caused by a magnetic field-induced decrease of the average bend angle in the aliphatic spacers connecting the rigid mesogenic units of the dimers

A fibre forming smectic twist-bent liquid crystalline phase

We demonstrate the nanostructure and filament formation of a novel liquid crystal phase of a dimeric mesogen below the twist–bend nematic phase. The new fibre-forming phase is distinguished by a short-correlated smectic order combined with an additional nanoscale periodicity that is not associated with density modulation

Similarities and differences between molecular order in the nematic and twist-bend nematic phases of a symmetric liquid crystal dimer

The order parameter, Szz, where z is the para axis of the difluoroterphenyl groups in DTC5C9, have been obtained from chemical shift anisotropies measured by ¹³C – {¹1H} NMR experiments at temperatures throughout the nematic, NU, and twist-bend nematic, NTB, phases shown by this compound. The order parameter temperature profiles are unusual in having a maximum value in the NU phase and then decreasing until the NTB phase is reached. There is a small discontinuity (~2%) in Szz at T_(NN_TB )and then a gradual decrease until a new phase appears. This behaviour is interpreted as revealing a temperature-dependent tilting of local directors in both phases away from the applied magnetic field direction. In the enantiomorphic twist-bend phase this tilt is consistent with the structure of the phase as a helical arrangement of local directors, whilst in the high-temperature non-chiral nematic the tilt must involve a non-chiral arrangement. It is proposed that in both phases the tilting of directors has a common origin in the bent shape of the molecules

Second harmonic light scattering induced by defects in the twist-bend nematic phase of liquid crystal dimers

The nematic twist-bend (NTB) phase, exhibited by certain thermotropic liquid crystalline (LC) dimers, represents a new orientationally ordered mesophase -- the first distinct nematic variant discovered in many years. The NTB phase is distinguished by a heliconical winding of the average molecular long axis (director) with a remarkably short (nanoscale) pitch and, in systems of achiral dimers, with an equal probability to form right- and left-handed domains. The NTB structure thus provides another fascinating example of spontaneous chiral symmetry breaking in nature. The order parameter driving the formation of the heliconical state has been theoretically conjectured to be a polarization field, deriving from the bent conformation of the dimers, that rotates helically with the same nanoscale pitch as the director field. It therefore presents a significant challenge for experimental detection. Here we report a second harmonic light scattering (SHLS) study on two achiral, NTB-forming LCs, which is sensitive to the polarization field due to micron-scale distortion of the helical structure associated with naturally-occurring textural defects. These defects are parabolic focal conics of smectic-like ``pseudo-layers", defined by planes of equivalent phase in a coarse-grained description of the NTB state. Our SHLS data are explained by a coarse-grained free energy density that combines a Landau-deGennes expansion of the polarization field, the elastic energy of a nematic, and a linear coupling between the two

Analisis Pendapatan USAhatani Cabai Di Desa Antapan (Studi Kasus Di Desa Antapan, Kecamatan Baturiti, Kabupaten Tabanan)

The title of this research is "Farming Income Analysis Antapan Chili in the village" (A Case Study in the village of Antapan, District Baturiti, Tabanan). This study aims to determine the amount of income received by Farmers Group Chili Setia Makmur as the respondent. The results showed revenue Chili Farmers Group Setia Makmur from farming Rp 86.186 million, - per acre per one growing season, with R / C ratio of 20.4. This shows that Chili farming in the village Antapan highly efficient and profitable, so it plays a role for members of the Farmers Group revenue Chili Setia Makmur. Based on the research results, it is suggested that Chili Farmers Group Setia Makmur retaining farming results, by developing procedures for processing Chili better

Faktor-faktor Yang Mempengaruhi Kunjungan Wisatawan Di Taman Hutan Raya Ngurah Rai

Ngurah Rai Grand Forest Park is a part of Tourism Area of Serangan Island in Benoa Bay. It is quite attrative for the foreign and local tourists. The dominant potential of ecotourism is the mangrove forest scene and the activities of traditional ceremoney in the forest. The quantity of visiting to Ngurah Rai Grand Forest Park are effected by some factors, those are ticket price, services, infrastructure and natural tourist attraction.The research was conducted on May – June 2015 in Ngurah Rai Grand Forest Park . The research aimed to know (1) the performance of Ngurah Rai Grand Forest Park; (2) which factor of the four factors (ticket price, services, infrastructure, or natural tourist attraction factor) had the highest effect to the number of tourist visitor in Ngurah Rai Grand Forest Park. This research used multiple linear regression method. Respondents were 104 visitors which were choosen by accidental sampling.The research showed that (1) the performance of Ngurah Rai Grand Forest Park: the visitors said that the entrance tickets is too expensive, because most of the visitor are stundent that can’t afford the price. The visitors also said that the services were very poor, they only give the tickets to the visitors without any other services. Regarding the infrastructure, the visitors said that the infrastructures were very poor, a lot of the wooden tracks were broken. And for the natural tourist attraction the visitors said that they were already saturated with the existing object. (2)The factor that give the significant effect to the visiting number were the ticket price, and the natural tourist attraction.

Ibm Untuk Kelompok Ternak Ikan Nila ‘Mina Karya’ Dan Irt ‘Mina Lestari’ Di Desa Selisihan, Kabupaten Klungkung

Selisihan village in Klungkung regency, Bali Province has 141.6 hectares area of agricultural land or 60% of the total area of the village which reached 236 hectares. The dominance of the agricultural sector does not necessarily make the villagers only rely on the agricultural sector, but groups of cattle cultivation are also actively utilizing non-agricultural land to be an alternative potential business. “Mina Karya" is a group of tilapia cultivation that facing problems in management of fish cultivation, especially regarding high mortality rate and uneven growth. While "Mina Lestari" is a home industry that proccessing of refined products of tilapia also facing cluttered productionarea and production process’s constraints related to the availability of production facilities. Both groups have an inability to increased production capacity and lack of knowledge on small business management and bookkeeping. The solutions are offered to "Mina Karya†by providing guidance and counseling training on seed selection,breeding technique and application of monoculture methods. For “Mina Lestariâ€, the activities carried out in renovated the production area which includes floor and wall works and repaired electrical installation. Additional equipments and supplies also given in order to assisting group in products diversification, particulary in waste product processed (head and bones of tilapia). Both groups will also get assistance and training in management and administration bookkeeping for small businesses.