Rancang Bangun Sistem Distilasi Air Laut Tenaga Surya Tipe Double Slope Dengan Penambahan Pelat Absorber Bentuk Gelombang Segitiga Dan Reflektor Internal

Metode distilasi tenaga surya merupakan salah satu metode pemurnian air yang dapat diterapkan untuk mengatasi masalah keterbatasan sumber air bersih yang terjadi di Indonesia. Penelitian ini bertujuan meningkatkan efisiensi dari alat distilasi tenaga surya dengan menambahkan pelat absorber bentuk gelombang segitiga dan reflektor internal di dalam bak penampungan alat distilasi tenaga surya. Sistem distilasi air laut tenaga surya telah dibuat dengan ukuran 0.75 × 0.50 m2 dari papan kayu dengan ketebalan 0.01 m. Kemiringan kaca penutup 35° sehingga kedua sisi samping memiliki tinggi 0.60 m. Bak penampungan dibuat dari pelat aluminium dengan ukuran 0.63 × 0.39 × 0.17 m 3 dan serbuk gergaji digunakan sebagai isolator. Pelat Absorber berbentuk gelombang dengan ukuran keseluruhan 0.63 × 0.39 m2 dibuat dari pelat aluminium dan memiliki 6 gelombang dimana masing-masing gelombang memiliki ukuran alas dan tinggi yaitu 0.06 dan 0.02 m. Produktivitas maksimum yang diperoleh pada pengujian sistem distilasi air laut tenaga surya dengan penambahan pelat absorber berbentuk gelombang segitiga sebanyak 529 mL dimana penggunaan pelat absorber berbentuk gelombang segitiga dapat meningkatkan produktivitas air tawar sebesar 24.67 % dibandingkan dengan sistem distilasi air laut tenaga surya konvensional. Efisiensi maksimum yang diperoleh dari hasil pengujian sistem distilasi air laut tenaga surya dengan penambahan pelat absorber berbentuk gelombang segitiga adalah 17.31 %. Berdasarkan hasil pengujian, disimpulkan bahwa penggunaan pelat absorber berbentuk gelombang segitiga dapat meningkatkan produktivitas dan efisiensi dari sistem distilasi air laut tenaga surya. ======================================================================================================================== Solar distillation is one method of water purification that can be applied to overcome the problem of limited fresh water resources in Indonesia. This study aims to improve the efficiency of solar still by adding the triangular waveform absorber plate and internal reflector in the basin of solar still. Solar distillation of sea water has been fabricated with size 0.75 × 0.50 m2 of wooden frame with a thickness of 0.01 m. The inclination of glass cover is 35° so the both of side has height 0.06 m. The basin of solar still made of aluminum plate with size 0.63 × 0.39 × 0.17 m3 and sawdust as insulator. The triangular waveform absorber plate with overall size of 0.63 × 0.39 m2 has been made using aluminum plate with 6 waveform and each of it has base and height of 0.06 and 0.02 m, respectively. Maximum productivity obtained on testing solar still by adding the triangular waveform absorber plate was 529 mL and it was found that the use of triangular waveform absorber plate can be improved the productivity of freshwater by 24.67% compared to conventional solar still. The maximum efficiency obtained from the testing of solar still by adding triangular waveform absorber plate was17.31%. Based on the test results, it concluded that the adding of triangular waveform absorber plate can improve the productivity and efficiency of the solar distillation of sea water

A comparative study of the decomposition of Rhizophora racemosa and Nypa fruticans of the great Kwa River, Cross River State, Nigeria

Mangroves are specialized marine ecosystem which is highly productive. They act as shelter, breeding and nursery grounds for a variety of Marine and brackishwater invertebrates and fishes. Some of the dominant plant species in mangrove vegetation of Nigerian coastline are Rhizophora species and Nypa fruticans. Studies were conducted on the decomposition of Rhizophora species and N. fruticans. The objective was to compare their decomposition rates and proffer informed management decisions. Decomposition rates of the two were monitored for 112 days using litter box experiment. Eight litter boxes were stocked with 10g of leaves of each species and two boxes containing the respective plants species were removed and examined for dry matter, carbon and nitrogen contents. There was no significant difference in the rates of decomposition of Rhizophora and N. fruticans leaves (p~.0.05) even though N. fruticans showed slightly higher rate of decomposition than Rhizophora. The linear relationship between the loss in dry matter and number were expressed as Y= 10.1-0.080x in N.fruticans, and Y=9.0-0.073x in Rhizophora sp. It was concluded that the argument in favour of the eradication of N.fruticans for the thriving of Rhizophora is inaccurate. Containment of the population rather than control is the logical strategy for the management of the riparian vegetation in the face of climate change

Elemental concentration and size relationship in African cuttlefish Sepia bertheloti, from the coastal waters of Qua Iboe River, Nigeria

Ten specimens of African cuttlefish, Sepia bertheloti, from the coastal waters off Qua Iboe River, Southeast Nigeria, were analyzed for the relationship between the concentration of the elements and the size of the species. Energy Dispersive X-ray fluorescence technique was employed to determine the elemental composition of the species. Eleven elements were identified in the body of cuttlefish. These were Chlorine, Strontium, Potassium, Calcium, Bromine, Iron, Copper, Zinc, Manganese, Nickel and Selenium of these elements, the concentration of calcium, potassium. Copper and strontium had a positive correlation with the weight, while the concentrations of manganese, nickel, chlorine, iron were negatively correlated with their weights. However, only manganese had a significantly negative correlation (p<0. 05). Bromine and zinc had no correlation with the weights of the species. There also existed a significant positive correlation between Ca and K, Se and Ni, Cu, Br and Zn and St and K. We conclude that African cuttlefish, irrespective of size is a rich source of nutritional elements and is especially recommended for pregnant women and for all age groups

STRATEGI INDEX CARD MATCH PADA MODEL TEAMS GAMES TOURNAMENT (TGT) DALAM MENINGKATKAN HASIL BELAJAR FISIKA

Strategi pembelajaran yang sering digunakan oleh guru fisika dalam pelaksanaan pembelajaran lebih didominasi oleh metode ceramah dengan media pembelajaran hanya berupa buku paket dan jarang dilakukan praktikum karena minimnya peralatan laboratorium IPA. Penggunaan model pembelajaran yang monoton serta minimnya kegiatan praktikum berdampak kepada  rendahnya minat dan motivasi belajar peserta didik sehingga ketuntasan hasil belajar peserta didik mengalami penurunan. Tulisan ini bertujuan untuk mendeskripsikan kemampuan guru dalam mengelola pembelajaran, keterampilan kooperatif peserta didik, ketuntasan indikator hasil belajar, ketuntasan hasil belajar, dan respon peserta didik terhadap proses pembelajaran dengan menerapkan strategi Index Card Match dalam model kooperatif tipe Teams Games Tournament (TGT). Jenis penelitian ini adalah penelitian deskriptif design dengan model penelitian one group pretest posttest. Sampel penelitian adalah kelas XI MIA 3 SMA Negeri 9 Kupang. Instrumen penelitian menggunakan lembar pengamatan pengelolaan pembelajaran, tes hasil belajar kognitif, penilaian hasil belajar (afektif dan psikomotor), lembar pengamatan keterampilan kooperatif peserta didik dan lembar isian respon peserta didik. Hasil penelitian menunjukkan bahwa kemampuan guru dalam mengelola pembelajaran berada dalam kategori cukup baik, keterampilan kooperatif peserta didik berada pada kategori sangat baik, indikator hasil belajar berada pada kategori tuntas, hasil belajar peserta didik berada pada kategori tuntas, dan respon peserta didik terhadap pelaksanaan pembelajaran berada pada kategori sangat baik

PENGGUNAAN SIMULASI PHET DAN E-EVALUATION BERBASIS HOT-POTATOES UNTUK MENINGKATKAN PEMAHAMAN KONSEP EFEK FOTOLISTRIK DAN MINAT BELAJAR CALON GURU FISIKA

ABSTRAKPenelitian ini bertujuan untuk mengetahui peningkatan pemahaman konsep dan minat belajar mahasiswa calon guru fisika setelah menggunakan simulasi PhET dan e-evaluation berbasis Hot Potatoes pada materi efek fotolistrik. Penelitian ini menggunakan desain penelitian One-Group Pretest-Posttest Design, instrumen yang digunakan berupa soal tes pemahaman konsep dan angket minat belajar. Hasil penelitian menunjukkan bahwa rata-rata pemahaman konsep pada pre test sebesar 47%  dengan kategori sedang dan post test sebesar 82% dengan kategori sangat tinggi. Nilai N-Gain pemahaman konsep mahasiswa calon guru fisika sebesar 0,66 dengan kategori sedang sedangkan rata-rata minat belajar mahasiswa calon guru fisika sebesar 83% dengan kategori sangat tinggi. Hasil penelitian menunjukkan bahwa penggunaan simulasi PhET dan e-evaluation berbasis Hot-Potatoes dalam pembelajaran fisika modern sub bab efek fotolistrik berkontribusi pada peningkatan pemahaman konsep dan minat belajar yang tinggi dari mahasiswa calon guru fisika. Kata kunci: simulasi PhET; hot potatoes; efek fotolistrik; pemahaman konsep; minat. ABSTRACTThis study aims to determine the improvement of concept understanding and learning interest of prospective physics teacher students after using PhET simulation and e-evaluation based on Hot Potatoes on photoelectric effect material. This study used a One-Group Pretest-Posttest Design research design, the instruments used were concept understanding test questions and learning interest questionnaires. The results showed that the average understanding of concepts in the pre-test was 47% with a moderate category and the post-test was 82% with a very high category. The N-Gain value of conceptual understanding of prospective physics teacher students is 0.66 with a moderate category. In contrast, the average learning interest of prospective students is 83% with a very high category. The results showed that the use of PhET simulation and e-evaluation based on Hot-Potatoes in learning modern physics of photoelectric effect sub-chapter contributed to the improvement of concept understanding and high learning interest of prospective physics teacher students. Keywords: PhET simulation; hot potatoes; photoelectric effects; concept understanding; interests

On modeling two immune effectors two strain antigen interaction

In this paper we consider the fractional order model with two immune effectors interacting with two strain antigen. The systems may explain the recurrence of some diseases e.g. tuberculosis (TB). The stability of equilibrium points are studied. Numerical solutions of this model are given. Using integer order system the system oscillates. Using fractional order system the system converges to a stable internal equilibrium. Ulam-Hyers stability of the system has been studied

Perancangan Video Dokumenter Tentang Wisata Kuliner Ikan Bakar Di Kota Makassar

Ikan Bakar Makassar Makassar merupakan Kuliner yang patut di coba jika kita berkunjung ke Makassar. ikan bakar sendiri memiliki beragam jenis masakan seperti kaneke dan bolu dan sambal. namun di luar semua kelebihannya kuliner ini masih kalah pamor dengan kuliner khas makasassar lainnya seperti Coto Makassar. berdasarkan survei dan observasi langsung terhadap hal-hal yang berkaitan dengan ikan bakar dapat diperkirakan bahwa tidak banyak orang dari luar kota yang mengetehaui tentang kuliner ikan bakar, oleh karena itu, dibuatlah video dengan program dokumenter kuliner yang bertemakan ikan bakar Makassar dengan nuansa yang menyenangkan dan menarik melalui perjalanan di laut mencari ikan sampai dengan bermain di pulau samalona dengan bantuan metode analisis kualitatif. Tujuan video ini adalah membantu memperkenalkan ikan bakar kepada semua orang yang berada diluar kota Makassar sehingga mereka tertarik untuk datang ke Makassar dan mencoba kuliner tersebut

Optimizing the drying conditions of date plum (Diospyros lotus L.) to conserve its phenolic content and antioxidants for preparing a highly bioaccessible polyphenol-rich tea

This is the final version. Available from Springer via the DOI in this record. Data availability: All data supporting this study are included in this manuscript.Date plum (Diospyros lotus L.) fruits are a good source of bioactive compounds and antioxidants. Drying can increase the shelf life of the fruit and its applications in the food development industry. Optimizing the drying conditions can help to produce prime-quality dried date plum fruits and conserve nutrients including phytochemicals. This study used a two-factor graphics-optimal design to optimize convective drying considering the air velocity and drying temperature of date plum fruits. The independent factors considered included drying temperature (43.78–86.21 °C) and air velocities (0.54–1.96 m/s), and the responses included total phenolic content (TPC), total favonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity of date plum fruit. The optimized drying conditions (68 °C and 1.75 m/s) resulted in desirable TPC, TFC, FRAP, and DPPH values. The fndings indicated that long drying time at low temperatures signifcantly decreased the phenolics and antioxidants. Date plum tea with diferent decoction times (5, 10, and 15 min) was prepared from fruits dried at optimum conditions. A decoction time of 5 min resulted in the highest catechin, vanillic, epicatechin, syringic acid, and quercetin-3-glucoside content, which were 2.45±0.04, 11.06±0.11, 22.03±0.11, 12.95±0.08, and 9.37±0.10 mg/L; respectively. In vitro gastrointestinal digestion revealed that the tea product can be a source of highly bioaccessible (>80%) gallic acid, catechin, vanillic acid, and quercetin-3-glucoside. Applying optimized drying conditions to dehydrate date plum fruit can be useful in preparing a highly bioaccessible polyphenol-rich tea

Cefotaximase (CTX-M) and quinolone resistance genes (qnr) with additional antimicrobial resistance mechanisms in commensal Escherichia coli from healthy pigs

Concerning the importance of food producing animals as potential reservoirs of enteric bacteria with clinically relevant antimicrobial resistance traits, we tested the prevalence of extended-spectrum β-lactamase (ESBL)-producing and fluroquinolone resistant E. coli from pigs in order identify multiple resistance mechanisms circulating in pig farms in Hungary and Croatia with special regards to plasmid mediated genes encoding cefotaximases (CTX-M) and quinolone resistance (qnr). For this purpose, faecal samples were collected from pigs representing three farms from Hungary and six farms from Croatia with 45 and 60 samples respectively. Farms were located in separate regions of the countries. Cefotaxime or nalidixic acid resistance were used as prime markers for the isolation of multiresistant E. coli strains. A second selection was based on resistance to additional antimicrobials (i.e. gentamicin) aiming to reduce the collection to isolates with representative multiresistance phenotypes. In several cases more than two different multiresistance phenotypes have been isolated from the same pig, which were considered as independent E. coli isolates. This collection of multidrug resistant E. coli contained 139 strains and was tested for the presence of blaCTX-M and qnr genes by PCR. Selected isolates carrying genes blaCTX-M and/or qnr are being subjected for confirmation and further typing of antimicrobial resistance genes by using the PCR-microarray AMR05. Cefotaxim resistant E. coli have been detected in one Hungarian and one Croatian farm representing 17% of all pigs tested. In majority of the strains, the plasmid-related resistance phenotypes such as ampicillin, cefotaxim, gentamicin and tetracycline occurred in multiple combinations. In 11% of the strains the coexistence of Ctx-Nal phenotypes was detected, together with the presence of the cefotaximase gene blaCTX-M. E. coli strains with nalidixin resistance phenotype have been predominantly (70%) characterizing healthy pigs independently from the farm and country of isolation. Ciprofloxacin resistant strains occured on one farm only. The plasmid-mediated fluoroquinolone resistance gene qnrS was identified in 11% of the strains, with or without the nalidixin-ciprofloxacin resistant phenotype, while genes qnrA and qnrB were absent. Overall, our results lead to conclude that multiresistant commensal E. coli strains carrying plasmid-mediated CTX-M type cefotaximase and/or quinolone resistance genes in different combinations are widespread on some pig farms but much less on others, most likely reflecting differences in use of antimicrobials. Ama Szmolka is a holder of János Bolyai Stipend of the Hungarian Academy of Sciences

Drying date plum (Diospyros lotus L.) fruit: Assessing rehydration properties, antioxidant activity, and phenolic compounds

This is the final version. Available on open access from Wiley via the DOI in this recordDate plum (Diospyrus lotus L.) is an edible fruit from the Ebenaceae family, rich in nutrients, and having tremendous medicinal properties. This paper attempted to show the influence of different parameters of convective drying such as temperature (50, 60, 70, and 80°C) and air velocity (0.5, 1.0, and 1.5 m/s) on the shrinkage and microstructure, rehydration properties, antioxidant activity, and phenolic compounds of date plum. The drying caused significant changes in the color, actual size, and distribution of the fruit cells of date plum. The total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) of fresh date plum were 0.81 ± 0.00 mg GAE/g, 0.23 ± 0.10 mg ECE/g, 7.15 ± 1.09 mmol ISE/g, and 14.92 ± 0.88 mmol/TE, respectively. The drying at 70°C had the highest values of TPC, TFC, gallic acid, chlorogenic and syringic acids, catechin, quercetin-3-glucoside, resveratrol, and DPPH. The drying air velocities showed no significant effects on the antioxidant contents and the antioxidant activity. Of the models applied to the drying kinetics, the Midilli model was found as the best model to describe the drying kinetics of date plum. In addition, the Weibull model was found as the most successful among the models applied to the rehydration kinetics of date plum. According to the achieved findings, the convective drying temperature of 70°C is the optimum temperature to produce the dehydrated date plum. Practical Application This work has revealed the drying conditions responsible for preserving the phenolic compounds, total flavonoid content, and antioxidant features of D. lotus L. The study found the optimum drying conditions, and Midilli and Weibull models were the most fitted models to describe the drying and rehydration behaviors of D. lotus L. fruits, respectively. The drying provides a reasonable value of the possibility of continuous consumption of the fruits dried afforded on off-seasons. The dried fruits are widely used for multipurpose and have been extensively used in food industries due to their rich nutraceutical and antioxidant compounds