Dalton

This paper was written to investigate the order of discoveries made in chemistry leading up to the discovery of the periodic table. New experimental techniques, such as the pneumatic trough, voltaic pile, spectroscopy, and potassium analysis led to the discovery of many new elements and their properties which enabled the discovery of the periodic table. The discoveries led to the demise of the classical theory of the elements, to the end of the phlogiston theory and to the creation of the modern ideas of the elements and of the atomic theory. The paper shows the discoveries were made in a necessary and inevitable order with new experimental techniques leading to the discovery of new elements which eventually led to the discovery of the periodic table.

At the end of the Pleistocene, Dalton hunter-gatherers substantially altered their technology by crafting points with serrated, beveled, and tapered blade margins. The functions of these attributes have been the focus of a long-held debate. Some archaeologists argue that the variation was the result of resharpening and use in varied tasks, like cutting-showing an adaptive shift to processing smaller game like deer. Other researchers suggest these new attributes were designed from the outset for the single functional use as projectiles. In this study, we use actualistic experiments to build analogues for interpreting microscopic usewear traces on an archaeological Dalton point assemblage from the Brand site, Arkansas. We then consider changes in point functionality within the broader context of the organization of Dalton lithic technology and how these changes reflect adaptations to the emerging Holocene environment.

Sabun cair merupakan salah satu jenis pembersih yang cukup banyak digunakan di dalam aspek kehidupan. Material ini berfungsi sebagai bahan penghilang kotoran dan lemak pada berbagai perkakas. Tujuan dilaksanakannya penelitian ini adalah untuk dasar pengaturan viskositas sabun cair bagi penelitian-penelitian selanjutnya. Surfaktan Sodium Lauril Sulfat (SLS) digunakan sebagai bahan baku utama dan garam NaCl sebagai pengatur viskositas. Konsentrasi NaCl yang digunakan dalam penelitian ini dimulai dari 0.45 % wt hingga 2.2% wt. Metode yang digunakan adalah metode reaksi batch. Hasil penelitian menunjukkan terjadi peningkatan viskositas sabun cair dari 300 cps hingga 5000 cps. Oleh karenanya, pengaturan viskositas dapat dilakukan dengan menggunakan konsentrasi garam sesuai kebutuhan.

Penelitian ini bertujuan untuk membandingkan hasil belajar siswa yang dibelajarkan dengan 2 cara berbeda. kelompok eksperimen dibelajarkan dengan menggunakan media kartu isomer, sedangkan kelompok kontrol dibelajarkan tanpa menggunakan media kartu isomer. Penelitian ini menggunakan rancangan kuasi eksperimen berupa pretest posttest control group design. Data penelitian diperoleh dari tes hasil belajar yang terdiri atas 19 soal pilihan ganda. Data dianalisis menggunakan uji t. Hasil penelitian menunjukkan bahwa hasil belajar siswa yang dibelajarkan menggunakan media kartu isomer lebih baik daripada siswa yang dibelajarkan tanpa menggunakan media kartu isomer.

At the end of the Pleistocene, Dalton hunter-gatherers substantially altered their technology by crafting points with serrated, beveled, and tapered blade margins. The functions of these attributes have been the focus of a long-held debate. Some archaeologists argue that the variation was the result of resharpening and use in varied tasks, like cutting-showing an adaptive shift to processing smaller game like deer. Other researchers suggest these new attributes were designed from the outset for the single functional use as projectiles. In this study, we use actualistic experiments to build analogues for interpreting microscopic usewear traces on an archaeological Dalton point assemblage from the Brand site, Arkansas. We then consider changes in point functionality within the broader context of the organization of Dalton lithic technology and how these changes reflect adaptations to the emerging Holocene environment.