Articles
<![CDATA[Analisis Iteman dan model Rasch pada pengembangan instrumen kemampuan berpikir kritis peserta didik sekolah menengah kejuruan ]]>
<![CDATA[Sri Nuryanti]]>;
<![CDATA[Muhammad Masykuri]]>;
<![CDATA[E. Susilowati]]>
<![CDATA[ Jurnal Inovasi Pendidikan IPA Vol 4, No 2: October 2018 ]]>
Publisher : <![CDATA[Faculty of Mathematics and Natural Sciences, Universitas Negeri Yogyakarta ]]>
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DOI: 10.21831/jipi.v4i2.21442
<![CDATA[Tujuan penelitian ini menganalisis instrumen kemampuan berpikir kritis. Penelitian ini merupakan penelitian kuantitatif. Data diperoleh dengan mengembangkan instrumen penilaian kemampuan berpikir kritis. Responden sebanyak 90 peserta didik yang diambil dari 3 SMK yang ada di kota Surakarta. Analisis data menggunakan perangkat lunak (software) analisis Iteman versi 3.0 dan Winstep versi 3.73. Metode yang digunakan dalam analisis ini yaitu metode tes klasik yaitu Iteman dan pemodelan Rasch. Hasil analisis dengan pemodelan Iteman diperoleh nilai Alpha Cronbach 0,80 berarti reliabilitas dari soal ini tinggi. Sedangkan dengan model Rasch Alpha Cronbach 0,74 berarti reliabilitas antara person dan item, sedangkan reliabilitas item 0,95 yang berarti item instrumen sangat bagus. Validitas item 0,93 menunjukkan soal dapat mengukur dan diperkuat dengan separation 4,34 item soal ini mempunyai sebaran respon yang baik. Instrumen kemampuan berpikir kritis dapat digunakan untuk penelitian selanjutnya. Iteman and rasch model analysis on the development of critical thinking instruments for vocational school students AbstractThe aimed of this study is to analyze the instrument of critical thinking skills. This research is quantitative research. Data was obtained by developing instruments for assessing critical thinking skills. Respondents were 90 students that taken from 3 Vocational Schools in Surakarta. Data analysis was using Iteman analysis software version 3.0 and Winstep version 3.73. The method used in this analysis were the classic test method, iteman and rasch models. The results of the analysis with iteman modeling obtained the Alpha Cronbach value of 0,800 means that the reliability of this problem was high. Whereas with the Rasch Alpha Cronbach model 0,74 means the reliability between person and item, while the reliability of the item is 0.95 which means the instrument item was very good. The validity of item 0.93 shows that the problem can be measured and reinforced with separation 4,34 items this question has a good distribution of responses. The instrument of critical thinking skills can be used for further research.]]>
<![CDATA[GREEN SYNTHESIS OF SILVER NANOPARTICLES USING CHITOSAN HYDROLYSATE AS STABILIZING AGENT AND THEIR ANTIBACTERIAL ACTIVITY ]]>
<![CDATA[Endang Susilowati]]>;
<![CDATA[Maryani .]]>;
<![CDATA[Ashadi .]]>
<![CDATA[ Indonesian Journal of Pharmacy Vol 26 No 1, 2015 ]]>
Publisher : <![CDATA[Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia ]]>
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DOI: 10.14499/indonesianjpharm26iss1pp37
<![CDATA[Silver nanoparticles were successfully synthesized with chitosan hydrolysate as stabilizing agent at room temperature. Silver nitrate, glucose and sodium hydroxide were used as silver precursor, reducing agent and accelerator respectively. Chitosan hydrolysate was produced by enzymatic process with papain enzyme. Molecular weight of chitosan hydrolysate determined by viscosimetry methode based on Mark-Howink equation. The effect of molecular weight of chitosan hydrolysate as stabilizing agent and AgNO3 concentration toward surface plasmon resonance (SPR) of silver nanoparticle was investigated. It is also reported the antibacterial activity of silver-chitosan nanocomposites against Staphylococcus aureus and Escherichia coli. The products of silver nanoparticles were characterized by UV-Vis spectroscopy and transmission electron microscopy (TEM). The result showed that the formation of silver nanoparticles was shown by the appearance of surface plasmon resonance (SPR) at 403–421nm from the corresponding UV-Vis spectra. The molecular weight of chitosan hydrolysate affects the absorbance intensity and the wavelength of SPR. Silver nanoparticles were spherical in shape as identified by TEM images with size in range of 4–26nm. The silver nanoparticles have showed high antibacterial activity against Escherichia coli and Staphylococcus aureus.Key word: green synthesis, silver nanoparticles, chitosan hydrolysate, stabilizing agent, antibacterial activity]]>
<![CDATA[EFFECTIVENESS OF GUIDED DISCOVERY BASED THERMOCHEMISTRY MODULE TO TRAIN CRITICAL THINKING SKILLS BASED ON GENDER DIFFERENCES ]]>
<![CDATA[Andini Desikasari Nuraisyah]]>;
<![CDATA[Sulistyo Saputro]]>;
<![CDATA[Endang Susilowati]]>
<![CDATA[ Jurnal Tadris Kimiya Vol 5, No 1 (2020) ]]>
Publisher : <![CDATA[Department of Chemistry Education, UIN Sunan Gunung Djati Bandung ]]>
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DOI: 10.15575/jtk.v5i1.8149
<![CDATA[Critical thinking skills are important competencies that need to be developed in chemistry learning. This study aimed to determine the effectiveness of the guided discovery-based thermochemistry module in developing critical thinking skills based on gender differences. The subject of this research was 76 females and 20 males of class XI Mathematics and Nature Science from three high schools in Ponorogo, Indonesia. This study used one school for each category, namely high, medium, and low. The research method used a quasi-experimental design with one group pretest-posttest. The data analysis technique used T-test with SPSS 21 software. The result showed that the average increase in student scores or normality gain score (n-gain) was 0.5050 to 0.6362, which means students' critical thinking skills improved after the implementation of guided discovery-based thermochemistry modules. T-test result in high category schools obtained T count > T table (2.142> 2.032), which showed that there are significant differences between the critical thinking skills of female and male students. Meanwhile, T count and T table in medium category school were 1.353 and 2.034, respectively. T count and T table in low category school respectively 1.106 and 2.068. Analysis of T-test results in medium and low school categories can be written -T table < T count < T table, is means there is no significant differences between the critical thinking skills of female and male students. Thus, guided discovery-based thermochemistry modules are effectively applied to high, medium and low school categories.]]>
<![CDATA[Synthesin and Characterization Chitosan Film with Silver Nanoparticle Addition As A Multiresistant Antibacteria Material ]]>
<![CDATA[Endang Susilowati]]>;
<![CDATA[Sri Retno Dwi Ariani]]>;
<![CDATA[Lina Mahardiani]]>;
<![CDATA[Luthfia Izzati]]>
<![CDATA[ JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 6, No 3 (2021): JKPK (Jurnal Kimia dan Pendidikan Kimia) ]]>
Publisher : <![CDATA[Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret ]]>
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DOI: 10.20961/jkpk.v6i3.57101
<![CDATA[The synthesis of chitosan films with the addition of silver nanoparticles (AgNps) has been carried out in 2 stages. The first stage is to make colloidal silver nanoparticles with chitosan as a stabilizer and a reducing agent with NaOH as an accelerator and assisted by microwave irradiation. The second stage is to make a film from colloidal silver nanoparticles-chitosan by casting method. The formation of silver nanoparticles was identified using a UV-Vis spectrophotometer and TEM. Chitosan films with the addition of AgNps were characterized by chemical, physical and mechanical properties. Furthermore, the antibacterial activity was tested against multi-resistant bacteria ESBL and MRSA. The results showed that the formation of AgNps was indicated by the appearance of an absorption band at 400-413 nm with a size of less than 6 nm. The FTIR spectra showed that there was a slight shift at the 1604 cm-1 peak which indicated that the AgNps interacted with the NH2 group on D-glucosamine of chitosan. The films morphology with addition Ag NPs tends to be rough in surface and cross-sectional. The presence of AgNps tends to increase the swelling value, tensile strength and film elasticity. Chitosan film with the addition of silver nanoparticles has antibacterial activity against multi-resistant bacteria ESBL and MRSA. The anti-bacterial activity of the film was derived solely from the silver nanoparticles.]]>
<![CDATA[Preparation and Characterization of Chitosan-Avocado Seed Starch (KIT-PBA) Edible Film ]]>
<![CDATA[Endang Susilowati]]>;
<![CDATA[Ary Eny Lestari]]>
<![CDATA[ JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 4, No 3 (2019): JKPK (Jurnal Kimia dan Pendidikan Kimia) ]]>
Publisher : <![CDATA[Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret ]]>
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DOI: 10.20961/jkpk.v4i3.29846
<![CDATA[Chitosan is a biopolymer that has the advantage of being able to form films that are non-toxic which has great potential to form edible films. To improve the properties of edible films in the form of antioxidants, it is necessary to add other materials such as avocado seed starch. This study aims to determine the effect of the use of avocado seed starch on mechanical properties, degree of swelling and solubility of edible film chitosan-Avocado Seed Starch (Kit-PBA). This study uses a laboratory experimental method. Steps in this study are (1) extraction of avocado seed starch; (2) Making edible film Kit-PBA (mixing chitosan and avocado seed starch), heating and neutralizing) with a ratio between chitosan: avocado seed starch are at 50:50; 60:40; 70:30; 80:20; 90:10; 100: 0; (3) Characterization of Kit-PBA are (tensile strength and elongation) edible film mechanical properties, swelling test and solubility test. The results showed that the higher the concentration of chitosan in the Kit-PBA edible film, the tensile and elongation strength values would increase while the degree of swelling and solubility would decrease.]]>
<![CDATA[Preparation of Silver-Chitosan Nanocomposites Colloidal and Film as Antibacteri Material ]]>
<![CDATA[Endang Susilowati]]>;
<![CDATA[Mohammad Masykuri]]>;
<![CDATA[Maria Ulfa]]>;
<![CDATA[Dyah Puspitasari]]>
<![CDATA[ JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 5, No 3 (2020): JKPK (Jurnal Kimia dan Pendidikan Kimia) ]]>
Publisher : <![CDATA[Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret ]]>
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DOI: 10.20961/jkpk.v5i3.46711
<![CDATA[Colloidal nanocomposites silver-chitosan have been made. Silver nanoparticles were produced by chemical reduction methods assisted microwave irradiation using chitosan from crab shells as a reducing agent and stabilizer, AgNO3 as a precursor and NaOH as an accelerator. This study investigated AgNO3 concentration toward localized surface plasmon resonance (LSPR) phenomenon of nanocomposites colloidal. The size and shape of the silver nanoparticles were confirmed by TEM. Furthermore, the stability of the storage was observed for twelve weeks. Colloidal and film nanocomposites silver- chitosan have been made by casting method by drying at room temperature. After that, the film characterization was carried out, including swelling with gravimetry methods and surface morphology using scanning electron microscopy (SEM). Diffusion methods tested colloid antibacterial activity and silver-chitosan nanocomposite film’s against E. Coli and S. Aureus. The results showed that the formation of silver nanoparticles was identified by the LSPR absorption band's appearance at 413-419 nm. The increasing of AgNO3 concentration increased the intensity of the LSPR absorption band. Silver nanoparticles with sizes of about 3-9 nm are spherical. The silver nanoparticles were stable at 12 weeks of storage. The higher AgNO3 concentration tends to increase the swelling of the film. The surface of the silver-chitosan nanocomposite film’s was rougher than that of the chitosan film. The higher the silver nanoparticle concentration, the higher the colloid and film antibacterial activity against E. Coli and S. Aureus.]]>
<![CDATA[Examining the Content Validity of Android-Based Augmented Reality Media for Chemical Bonding using Rasch Model ]]>
<![CDATA[Sri Yamtinah]]>;
<![CDATA[Sri Retno Dwi Ariani]]>;
<![CDATA[Martha Andriyanti]]>;
<![CDATA[Sulistyo Saputro]]>;
<![CDATA[Endang Susilowati]]>;
<![CDATA[Ari Syahidul Shidiq]]>;
<![CDATA[Dimas Gilang Ramadhani]]>;
<![CDATA[Isma Aziz Fakhrudin]]>
<![CDATA[ Jurnal Penelitian Pendidikan IPA Vol. 7 No. SpecialIssue (2021): December ]]>
Publisher : <![CDATA[Postgraduate, University of Mataram ]]>
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DOI: 10.29303/jppipa.v7iSpecialIssue.1094
<![CDATA[21st-century learning presents chemistry teachers with new challenges in teaching abstract chemistry concepts with various technologies that continue to develop. One of the media that can visualize abstract chemical concepts is Augmented Reality (AR). AR media developed in chemistry learning needs to be valid so that it can be used properly. Therefore, this study aims to examine the validity of the Android-based AR media developed. Four education practitioners carried out the validation as experts, and 13 students participated as respondents. The instrument used is a questionnaire with a Likert scale. The data obtained were analyzed quantitatively with the Rasch model using the facet software. The results of the analysis show that the Exact Agreements are 41.10%, and the Expected Agreements are 42.20%. The most challenging aspect to achieve is media design, while profit is the most easily agreed-upon aspect. Based on this assessment, in the development of augmented reality media, it is necessary to pay attention to display aspects and 3D objects suitable for viewing a material so that it is easier for users to understand the material.]]>
<![CDATA[Synthesis of Silver-Chitosan Nanocomposites Colloidal by Glucose as Reducing Agent ]]>
<![CDATA[Endang Susilowati]]>;
<![CDATA[Triyono Triyono]]>;
<![CDATA[Sri Juari Santosa]]>;
<![CDATA[Indriana Kartini]]>
<![CDATA[ Indonesian Journal of Chemistry Vol 15, No 1 (2015) ]]>
Publisher : <![CDATA[Universitas Gadjah Mada ]]>
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DOI: 10.22146/ijc.21220
<![CDATA[Silver-chitosan nanocomposites colloidal was successfully performed by chemical reduction method at room temperature using glucose as reducing agent, sodium hydroxide (NaOH) as accelerator reagent, silver nitrate (AgNO3) as metal precursor and chitosan as stabilizing agent. Compared to other synthetic methods, this work is green and simple. The effect of the amount of NaOH, molar ratio of AgNO3 to glucose and AgNO3 concentration towards Localized Surface Plasmon Resonance (LSPR) absorption band of silver nanoparticles was investigated using UV-Vis spectrophotometer. The stability of the colloid was also studied for the first 16 weeks of storage at ambient temperature. The formation of silver nanoparticles was confirmed by the appearance of LSPR absorption peak at 402.4–414.5 nm. It is also shown that the absorption peak of LSPR were affected by NaOH amount, ratio molar AgNO3/glucose and concentration of AgNO3. The produced silver nanoparticles were spherical with dominant size range of 6 to 18 nm as shown by TEM images. All colloidals were stable without any aggregation for 16 weeks after preparation. The newly prepared silver-chitosan nanocomposites colloidal may have potential for antibacterial applications.]]>
<![CDATA[ACTIVITY TEST OF GUAVA (Psidium guajava L.) LEAF METHANOL EXTRACT AS CONTRACEPTION ANTIFERTILITY TO WHITE MICE (Rattus norvegicus) ]]>
<![CDATA[Sri Retno Dwi Ariani]]>;
<![CDATA[Endang Susilowati]]>;
<![CDATA[Elfi Susanti VH]]>;
<![CDATA[Setiyani Setiyani]]>
<![CDATA[ Indonesian Journal of Chemistry Vol 8, No 2 (2008) ]]>
Publisher : <![CDATA[Universitas Gadjah Mada ]]>
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DOI: 10.22146/ijc.21632
<![CDATA[The aim of this research is to know about if the guava (Psidium guajava L.) leaf methanol extract on 10.5 mg/mL and 21.0 mg/mL dossages indicate a positive test as contraception antifertility to white mice (Rattus norvegicus). The sample is guava leaf from Mungkid, Magelang Central of Java Indonesia. The animals experiment are the white mice on 140-300 g for female, 200-250 g for male and about 3 months of age in average. The steps of this research are : (1) preparing sample, i.e. washing, drying on to indirect sunlight and make the sample into powder, (2) isolation the guava leaf powder in soxhlet instrument with hexane, (3) evaporation the sample with rotary evaporator until guava leaf hexane extract produced, (4) maseration the sample with methanol, (5) evaporation the sample with rotary evaporator until guava leaf methanol extract produced, (6) conducting contraception antifertility activity test to guave leaf methanol extract on 10.5 mg/mL and 21.0 mg/mL dossages to mice white. The results of this research are guava leaf methanol extract on 10.5 mg/mL and 21.0 mg/mL dossages indicate a negative contraception antifertility test to white mice but in these dossages have indicated that an antiimplantation effect (the total natality of fetus is less than the total implantation site in mice white).]]>
<![CDATA[Pendampingan Produksi Mie Sayuran Kekinian sebagai Upaya Meningkatkan Penghasilan UMKM Makanan di Karanganyar Jawa Tengah ]]>
<![CDATA[Endang Susilowati]]>;
<![CDATA[Mohammad Masykuri]]>;
<![CDATA[Maria Ulfa]]>
<![CDATA[ Jurnal Abdi Masyarakat Indonesia Vol 2 No 3 (2022): JAMSI - Mei 2022 ]]>
Publisher : <![CDATA[CV Firmos ]]>
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DOI: 10.54082/jamsi.375
<![CDATA[Usaha Mikro, Kecil, dan Menengah (UMKM) berpotensi untuk dikembangkan di masa pandemi karena kemampuan menyerap tenaga kerja dan menggunakan sumberdaya lokal, serta usahanya relatif bersifat fleksibel. Salah satu usaha kecil yang menarik untuk dikembangkan adalah usaha mie yang telah menjadi komuditas yang digemari masyarakat. Adapun jenis mie yang potensial untuk dikembangkan pada UMKM berbasis makanan adalah mie sayuran. Berdasarkan observasi di UMKM mie kekinian dengan merk “Nyelekitz” yang dikelola oleh Ibu Yuli di Kabupaten Karanganyar Jawa Tengah, ada masalah utama yang perlu diselesaikan. Masalah utama yang dihadapi adalah mie dan bumbunya masih dibeli dari tengkulak dan hanya 1 varian mie saja. Oleh karena itu tim pengabdian UNS melakukan pelatihan dan pendampingan produksi mie dengan varian aneka mie sayuran kekinian. Adapun metode yang dilakukan oleh tim pengabdian adalah melalui pelatihan dan pendampingan kepada mitra pada pembuatan mie sayuran dan bumbunya. Setelah mitra mahir membuat mie sayuran dan layak untuk dipasarkan, maka tim pengabdian melakukan pendampingan dalam pengemasan. Dari kegiatan pengabdian yang telah dilakukan diperoleh hasil bahwa mitra telah trampil membuat mie sayuran dan membuat bumbu mie kekinian. Berdasarkan uji organoleptic, produk mie yang dihasilkan disukai dan sudah layak dipasarkan. Pemasaran produk mie dilakukan di kedai rumah dan online melalui WA grup. Dengan kegiatan pengabdian ini mitra merasa sangat terbantu dan telah meningkatkan omset penjualan dan pendapatan hasil usaha mie kekinian. ]]>
