1,634 research outputs found
IDENTIFIKASI KARAKTER MORFOLOGI DAN FISIKOKIMIA TALAS PUTIH (Xanthosoma sp) PADA BERBAGAI TIPE LINGKUNGAN PERTANAMAN
Penelitian ini telah dilaksanakan dari bulan November 2018 sampai dengan Januari 2019. Penelitian ini bertujuan untuk memperoleh informasi tentang karakter morfologi dan fisikokimia tanaman talas putih yang berpotensi untuk dijadikan sumber karbohidrat tambahan. Metode penelitian ini adalah metode survei dengan pengambilan sampel secara sengaja (purposive sampling). Data dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa karakter morfologi tanaman talas putih secara kuantitatif beragam, sedangkan secara kualitatif seragam. Pertumbuhan tanaman yang lebih baik pada tipe lahan tumpang sela dibandingkan pada tipe lahan terbuka dan ternaungi. Kandungan karbohidrat dan kalsium oksalat lebih tinggi pada lahan terbuka dengan nilai 35,23% dan 467,74 mg/100 g
Behavior of steel beams subjected to LTB at elevated temperature/Fire
When the steel beam is subjected to fire, there are great chances for the steel beam to decrease
its stiffness due to which the flexural and lateral torsional buckling capacity (LTB) properties
of respective steel beam affected. At an elevated temperature, there exist a non-linear stressstrain behavior of steel beam at an elevated temperature. The steel beam is subjected to fire
under different elevated temperatures in Finite Element Modeling tools and ANSYS to
investigate the behavior and changing properties during the elevated temperature. The FEM is
considered validated instead of experimentation for fire in laboratory because to get such high
temperature just for prototype or modeling is not achievable, thus, to study the behavior of steel
using modeling techniques. The specific modeling tools create an experimental model to study
by carrying the set of parametric studies. The steel beam is analyzed by changing the thermal
properties, mechanical and physical properties at an elevated temperature.
The main theme of this research congested only with lateral torsional buckling moment
capacity of I-beam and non-dimensional slenderness ratio. Buckling plays an important in the
stability of structures.
To investigate this, there are five cases while analyzing the I-Beam throughout the crosssection and at various locations when subjected to fire or elevated temperature.
1) Case 01: No fire or elevated temperature: In this case, the steel beam is analyzed
without having elevated temperature.
2) Case 02: Whole cross-section of the beam is subjected to fire or elevated temperature
of same nature. The reduction in physical properties are applied throughout the beam.
3) Case 03: The elevated temperature in the beam is subjected to whole bottom flange and
half of web in uniform way.
4) Case 04: In this case, the elevated temperature is subjected to top and bottom flange
and web at L/3.
5) Case 05: In this case, the elevated temperature is subjected to 1/3 of mid-span length
of the I-beam at the bottom flange and the lower half of the web.
The purpose and objective of this study to analyze how the steel beam behave in case of
subjected to fire, in different scenarios discussed above, on lateral torsional buckling capacity
(Mb,Rd). When different test is applied through FEM, then it came to know that the steel
specimen is getting failed under LTB irrespective of fire and end support condition. There exist
two kinds of buckling while studying; one is linear buckling analysis and nonlinear buckling
analysis. It is common observation that, with the increase in temperature, the length of the steel
beam also increases due to the phenomenon of expansion or contraction properties of steel in
an increasing or decreasing way of external temperature. By increase in the length of the steel
beam, the lateral buckling capacity and flexural strength decrease that may result in the collapse
of structure, thus this study is carried out to analyze this behavior to improve and suggest the
modifications while designing the structures based on fire loading. After doing the analysis,
the results are explained in a detailed way.
At an elevated temperature, there is reduction in strength of steel and stiffness of material with
which beam is made, i.e., stainless steel. As stainless steel is alloy of different material, so it
provides better retention as compared to carbon steel.
Stainless steel beams are capable of bearing more temperature because they have high value of
coefficient of thermal expansion as compared to carbon stee
Studies towards the total synthesis of DEM30355/A and related polyketides
PhD ThesisDEM30355/A 1 is a novel bioactive natural product polyketide isolated from an
Amycolatopsis bacteria. 1 shows antibacterial activity against several pathogenic Gram
positive bacteria, including methicillin-resistant Staphylococcus aureus. Thus we have
explored the total synthesis of 1 and a number of related polyketide natural products
(Figure 1).
Figure 1: Structure of DEM30355A 1.
In our first attempts towards the synthesis of target molecule 1 we examined several
synthetic routes towards a key intermediate 2. These routes included: (a) the synthesis of
Wittig product 3, followed by an unsuccessful attempt at a sterically challenging Baylis-
Hillman reaction with diethyl ketomalonate 4; (b) following the synthesis of 5, an attempted
Lewis acid catalysed Friedel-Crafts reaction between 1,4-dimethoxybenzene 6 and 5; and
(c) Heck coupling of 2-bromo-1,4-dimethoxybenzene 8 with 5. The best results were
obtained via route (c) although the yields from the Heck coupling were low, prompting us
to examine an alternative route (Scheme 1).
Scheme 1: Examined routes to key synthetic intermediate 2.
Abstract
iii
We then examined alternative synthetic approaches towards the aromatic ring A of
target molecule 1, based on the formation of the synthetic intermediate 9. Compound 11,
which contains the core substitution pattern needed to create ring A, was successfully
produced via an unusual bromination of 2,5-dihydroxybenzaldehdye 10. After considerable
optimisation we developed a method for the di-methylation of 11. Reduction of aldehyde
12 into corresponding alcohol 13 and subsequent protection of 13 with TBDMSCl gave 14
in a high yield. The synthesis of 9 was completed via a halogen-metal exchange reaction of
14 followed by trapping with DMF (Scheme 2).
Scheme 2: Synthesis of ring A.
Alongside our work towards the synthesis of 1, we have examined the total
synthesis of the polyketide natural product (-)-(3R)-5-hydroxymellein 15, starting from
the previously synthesised common intermediate 13. We have successfully synthesised
18, the deoxy-analogue of 15, via a halogen-metal exchange reaction of 16 followed by
ring opening of propylene oxide and followed by deprotection and cyclisationUmm Al-Qura Universit
Penerapan manajemen kurikulum pada kelas Unggulan di Madrasah Aliyah Negeri 1 Medan
Penelitian ini bertujuan untuk mengetahui penerapan manajemen kurikulum pada kelas unggulan di Madrasah Aliyah Negeri 1 Medan. Untuk mencapai tujuan ini peneliti menggunakan metode pengumpulan data dan analisis data yang mengacu pada kaidah-kaidah penelitian kualitatif. Prosedur pemilihan narasumber ditentukan berdasarkan pertimbangan keterlibatannya dalam penerapan manajemen kurikulum kelas unggulan di Madrasah Aliyah Negeri 1 Medan.
Pengumpulan data penelitian diperoleh dengan teknik observasi, wawancara dan studi dokumen. Hasil penelitian mengungkapkan temuan sebagai berikut. 1) Perencanaan kurikulum pada kelas unggulan disusun dengan melibatkan tim pengembang kurikulum yang terdiri dari kepala madrasah, wakil-wakil kepala madrasah, guru, komite madrasah, tenaga ahli dari dewan pakar Madrasah Aliyah Negeri 1 Medan, dan orangtua siswa. Langkah yang dilakukan adalah dengan menganalisis konteks dan kebutuhan serta mengidentifikasi standar nasional pendidikan. 2) Pengorganisasian kurikulum pada kelas unggulan dengan cara kepala madrasah memberdayakan wakil kepala madrasah bidang kurikulum dan wakil kepala madrasah bidang MGMP untuk melakukan penjadwalan dan pembagian tugas. 3) Pelaksanaan kurikulum pada kelas unggulan dilakukan dengan melakukan kegiatan pengawasan terhadap pelaksanaan kurikulum oleh kepala madrasah. Selain itu, kepala madrasah memberi wewenang kepada wakil kepala madrasah maupun guru untuk melakukan rapat kecil (breefing) pada setiap pagi. 4) Evaluasi kurikulum pada kelas unggulan dilakukan oleh kepala madrasah dibantu oleh wakil kepala madarasah bidang kurikulum. Evaluasi dilakukan dengan cara memeriksa dokumen kurikulum, wawancara, dan supervisi kelas. 5) Faktor pendukung penerapan kurikulum pada kelas unggulan adalah kerja sama tim pengembang kurikulum dan kerja sama antarguru dalam wadah MGMP, kualifikasi pendidikan guru, sarana dan prasarana yang memadai, dan keberadaan dewan pakar. Faktor penghambat penerapan kurikulum pada kelas unggulan adalah tanggung jawab akademik tenaga pengajar yang masih kurang, motivasi guru yang mengajar pada kelas unggulan, kesiapan siswa secara psikologis mengikuti pembelajaran, dan kurangnya pengawasan dari dewan pakar.
Hasil penelitian menunjukkan bahwa fungsi perencanaan dan evaluasi kurikulum pada kelas unggulan sudah berjalan sebagaimana mestinya. Akan tetapi fungsi pengorganisasian dan pelaksanaan kurikulum kelas unggulan belum sepenuhnya berjalan secara optimal
INCIDENCE OF POWDERY MILDEW ON CUCURBIT PLANTS IN KATSINA, NIGERIA
Present paper deals with the study of powdery mildew incidence on different cucurbits in Katsina city (Barhim Estate, Kofar Durbi, Kofar Sauri, Kofar Marusa and Low Cost), Nigeria. The finding shows that the areas infested with powdery mildew is one of the important disease of cucurbits. The Sphaerotheca fuliginea was identified to be the causal organism present on all observed cucurbits in the study. Highest frequency of disease was found in Kofar Sauri(79%) fallowed by Kofar Marusa (68%), Kofar Durbi (66%), Barhim Estate (65%) and the lowest frequency of occurrence of disease was found in Low Cost (55%).The intensity of the disease was moderate to severe in general but it was high in many fields, the area-wise variation was also noticed. On vegetables, the highest frequency of occurrence of powdery mildew disease was observed on L. cylindrica (76.4%) followed by C. moschata (60%), C. sativus (59.3%), C. vulgaris (53.9%) and lowest was found on C. melo (44.4%). The highest intensity of disease was found on C. moschata, followed by L. cylindrica, C. sativus, C. vulgaris and C. melo
Economic analysis and optimization for bio-hydrogen production from oil palm waste via steam gasification
Biomass steam gasification with in-situ carbon dioxide capture using CaO exhibits good prospects for the production of hydrogen rich gas. In Malaysia, due to abundance of palm waste, it is a good candidate to be used as a feedstock for hydrogen production. The present work focuses on the mathematical modeling of detailed economic analysis and cost minimization of the flowsheet design for hydrogen production from palm waste using MATLAB. The influence of the operating parameters on the economics is performed. It is predicted that hydrogen cost decreasing by increasing both temperature and steam/biomass ratio. Meanwhile, the hydrogen cost increases when increasing sorbent/biomass ratio. Cost minimization solves to give optimum cost of 1.9105 USD/kg with hydrogen purity, hydrogen yield, hydrogen efficiency and thermodynamic efficiency are 79.9 mol%, 17.97 g/hr, 81.47% and 79.85% respectively. The results indicate that this system has the potential to offer low production cost for hydrogen production from palm waste
Parametric study on the heating values of products as via steam gasification of palm waste using CaO as sorbent material
In Malaysia, due to abundance of oil palm waste, it is a good candidate to be used as a feedstock for syngas and hydrogen production. Biomass steam gasification is one of the promising methods for syngas production. This work focuses on the steam gasification with in-situ CO2 capture using CaO as absorbent materials for hydrogen production from palm oil empty fruit bunch (EFB). Three parameters (temperature, steam/biomass ratio and sorbent/biomass ratio) has been studied on the lower heating value (LHV) and higher heating value (HHV) of product gas. The results shows that the current study gives higher value of LHV at lower temperature of 823K. The higher value of LHV is obtained due to the lower concentration of CO2 caused by using CaO as sorbent material. Furthermore, CaO materials enhanced the concentration of concentration of the CO, H2 and CH4 in the product gas. The results are also compared against published data as well
Analisis penentuan waktu salat isya’ berdasarkan syafaq abyaḍ di Pulau Masalembu, Kabupaten Sumenep, Jawa Timur
Salat merupakan ibadah yang dimulai dengan takbīr al-Iḥrām dan diakhiri dengan salam sesuai dengan rukun dan syarat-syarat tertentu. Salat tidak bisa dilakukan dalam sembarang waktu, adanya ketentuan waktu yang telah termuat melahirkan pemahaman bahwa ketentuan waktu-waktu salat tersebut berkaitan dengan posisi Matahari pada bola langit. Tanda dalam penentuan waktu salat Isya yaitu menggunakan Syafaq. Syafaq merupakan percampuran cahaya siang dengan gelapnya malam ketika Matahari terbenam sehingga menghasilkan berbagai macam warna seperti kuning, orange, merah dan putih. Syafaq terbagi menjadi dua, syafaq aḥmar dan syafaq abyaḍ.
Permasalahan utama dalam pembahasan ini adalah hilangnya syafaq aḥmar sebagai landasan masuknya awal waktu salat Isya dengan ketinggian Matahari -18° masih dipertanyakan. Dalam penentuan awal waktu salat Isya Imam Syafii dan Imam Malik menggunakan syafaq aḥmar dan Imam Hambali dan Imam Hanafi menggunakan syafaq abyaḍ sebagai acuan masuknya awal waktu salat Isya. Jenis penilitian ini menggunakan metode kualitatif dengan jenis penelitian lapangan (Field Research) dengan sumber data primer adalah data dari Sky Quality Meter (SQM). Teknik pengumpulan datanya dilakukan dengan cara perekaman data kecerlangan langit di Pulau Masalembu. Polusi cahaya dan polusi udara sangat menganggu pengamatan terhadap hilangnya syafaq sehingga butuh banyak penelitian atau observasi terhadap hilangnya syafaq. Observasi syafaq membutuhkan tempat yang langsung bisa melihat ufuk barat. Dalam penelitian terbenamnya syafaq membutuhkan kondisi langit yang sangat gelap dan kondisi langit yang cerah pada saat Matahari terbenam sehingga dapat memaksimalkan perolehan data observasi syafaq. Pulau Masalembu sangat cocok dikarenakan kondisi langit malam berada pada 22.00 mag./arc sec2.
Dalam menentukan awal waktu Isya’ Kemenag RI menggunakan kriteria dengan ketinggian Matahari -18° dengan kondisi langit telah hilang syafaq aḥmar. Adapun dalam penelitian lapangan yang berlokasi di Pulau Masalembu, Kabupaten Sumenep, Jawa Timur. Penelitian ini menyimpulkan bahwa pada ketinggian Matahari -16° syafaq aḥmar telah hilang, dan ketinggian -18° syafaq abyaḍ telah hilang. Dengan demikian, menurut hemat peneliti penggunaan -18° yang telah ditetapkan Kemenag RI belum sesuai apabila digunakan di Pulau Masalembu
Impact of Brand Loyalty on Brand Extension
The key objective of this study is to explore the effects of different dimensions of brand loyalty towards the original brand on the evaluation of brand extensions. This was a primary research and questionnaire was distributed among 200 respondents and 183 were processed for analysis. The target respondents were the students of different universities of Islamabad and Rawalpindi, Pakistan. The scale was taken from the existing research (Hem and Iversen, 2003). SPSS was used to analyze the data. The result finds that there is positive and significant relationship between brand loyalty and brand extension. So on the bases of these results that all the hypotheses (H1, H2, H3, H4 and H5) are proved positively and significantly and affect the evaluation of brand extension.
Keywords: Brand Loyalty, Brand Extension, original bran
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