Particle mass, mobility, volatile mass fraction, effective density, mass concentration, mass-mobility exponent, and particle morphology were measured from soot generated from a premixed flame (McKenna burner) and an inverted diffusion flame over a range of equivalence ratios. It was found that the mass fraction of volatile material on the soot from the McKenna burner could be up to 0.83 at a high equivalence ratio, but there was no measurable volatile material on the soot from the inverted burner. The inverted burner can produce soot at different mass-mobility exponents, ranging from 2.23 to 2.54, over a range of global equivalence ratios of 0.53-0.67, while the mass-mobility exponent ranges from 2.19 to 2.99 for fresh soot and 2.19 to 2.81 for denuded soot for the McKenna burner at equivalence ratios of 2.0-3.75. Transmission electron microscopy analysis of inverted burner soot shows that a range of particle morphologies is present at a given global equivalence ratio, likely due to different local equivalence ratios and flame conditions in the diffusion flame. Primary particle diameter tends to increase with aggregate size, which could contribute to the mass-mobility exponent being well above 2.

The morphology and nanostructure of soot from different engines were studied. The soot samples were collected from a 1.9 L Volkswagen light-duty diesel (LDD) engine for two different fuel types [ultralow sulfur diesel (ULSD) and B20] and six speed/load combinations, as well as from a heavy-duty engine using a pilot-ignited high-pressure direct-injection (HPDI) natural-gas combustion system for three different speed/load combinations. Transmission electron microscopy (TEM) was employed to investigate the soot morphology by using alternative fractal measurement methods. The fractal dimensions (D f) were computed from the scaling of the projected aggregate dimensions with the number of primary particles ("LW" method) and two-dimensional pair correlation functions. For the soot collected from the LDD, it was found that the fractal dimensions are independent of fuel type, while a higher engine load slightly decreased D f. The soot produced by the HPDI exhibited a similar correlation between D f and engine load. The fractal dimension of the engine-emitted soot was measured in a range of 1.70-1.85 and the fractal prefactor k fLW of 1.08-1.39. Raman spectroscopy was used to characterize the soot nanostructure based on the degree of microstructural disorder. The Raman spectral analysis was done using two-band ("G" at ∼1578 and "D" at ∼1340 cm −1) and five-band (G, D1, D2, D3, and D4 at about 1580, 1350, 1500, 1620, and 1200 cm −1 respectively) combinations. For the soot sampled from the LDD, the results from both methods showed that B20 soot exhibited a greater structural disorder. Likewise, the Raman analysis of the soot from both engines also showed that the increase in engine load condition caused increases in the degree of the structural order of soot. The use of either D/G ratio or D1 width cannot distinguish between the HPDI and the LDD soot. However, on a plot of D/G versus D1, the data fall into distinct clusters. This may indicate the importance of using more than two spectral parameters to characterize the soot samples. Supplementary materials are available for this article. Go to the publisher's online edition of Aerosol Science and Technology to view the free supplementary files.

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<p>Dalam industri manufaktur <em>modern</em>, <em>3D Printer</em> dan <em>Laser Engraver</em> merupakan dua fungsi dasar yang dapat mewujudkan objek rancangan 3D sesuai dengan fungsi yang diinginkan secara cepat dan ekonomis. Meskipun demikian, secara umum dalam prakteknya seringkali kedua fungsi tersebut hanya dapat dipenuhi oleh dua jenis alat berbeda. Tentu saja hal ini akan berdampak pada tingginya biaya-biaya yang dikeluarkan oleh pelaku-pelaku industri manufaktur, baik dari segi biaya operasional, biaya pengadaan, waktu produksi, dan lain sebagainya. Oleh karena itu diperlukan perancangan alat berbiaya rendah yang dapat mengintegrasikan dua fungsi yaitu 3D <em>Printer</em> dan <em>Laser Engraving.</em> Dalam penelitian ini dilakukan perancangan sistem alat yang dapat mengintegrasikan fungsi 3D printer dan <em>Laser Engraver</em> dengan hanya memvariasikan <em>head</em> sehingga dalam penggunaanya, <em>head</em> dapat diganti dari <em>3D Printer</em> ke <em>Laser Engraver</em> dan juga sebaliknya. Pengujian fungsi 3D printer dilakukan berdasarkan fenomena <em>bridging</em>, <em>overhang</em>, dan <em>oozebane</em> melalui variasi parameter sehingga dihasilkan pengaturan optimal pada suhu <em>hotend</em> 185 °C, suhu <em>heated</em> <em>bed</em> 50 °C dan <em>feedrate</em> cetak 25 mm/min sehingga didapat akurasi dan kepresisian pada proses <em>3D Printer</em> dengan material PLA sebesar 0,1 mm. Sedangkan pada pengujian fungsi <em>Laser Engraver</em> didapat penandaan (<em>marking</em>) yang optimal pada jarak <em>head</em> laser 75 mm, sedangkan kecepatan gerak optimum pada material kardus sebesar 400 mm/min, dan material triplek pada 300 mm/min.<strong> </strong></p>

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Aquaponic is a combination hydroponic (cultivation of plants without soil) and aquaculture (fish growing) that promotes sustainable food production. In order to be adopted by general population, the design of aquaponics needs to be practical and economical. The main purpose of this community outreach is to design and introduce small-scale aquaponics system that can be used by homeowners with limited backyard. For this purpose, the community located at Kelapa Dua Tangerang was chosen as the main partner. The prototype of the small-scale aquaponics was then used as education and demonstration tool to encourage the community of Kelapa Dua Tangerang to adopt eco-friendly aquaponics cultivation system. The prototype of the aquaponics worked flawlessly with the water circulation inside the system was set at 0.046 litre/second. The water was used to supply adequate nutriens for water spinach, lettuce and pak choy which can be harvested in two months. In addition, this leafy greens can enhance the overall yard aesthetics. For the aquaculture, the catfish in the tank showed steady grow rate and healthy condition. In general, the education process can be considered successful as indicated by positive responses from the community (feedback score of 2.93 out of 4). From joint evaluation, the community excited with further development of the small-scale aquaponics.