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Topik - nandaz

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1
Biologi / Kelinci Playboy?
« pada: Desember 08, 2011, 10:33:32 AM »
Kenapa Playboy diidentikkan dengan kelinci? apakah Kelinci itu hewan yang suka menduakan pasangan....kalo ada alasan ilmiahnya tolong dikemukakan

Thanks b4... :kribo:

2
Matematika / [WANTED]Jurnal Matematika
« pada: Juli 27, 2011, 08:27:07 PM »
Mohon batuannya jika ada yang punya jurnal seputar matematika coba berbagi disini, saya lg cari bahan buat TA
atas perhatiannya saya ucapkan terimakasih banyak....
 ;)

3
Kesehatan / Sklerosis(Help!)
« pada: Pebruari 28, 2011, 08:25:53 PM »
Teman-teman, tolong bantuannya apa ada yang tau bagaimana menyembuhkan penyakit ini (kalo bisa tolong jelasin secara rinci mengenai Sklerosis, tentunya dengan bahasa yang mudah dimengerti oleh pasien). Bagaimana cara mengatasinya tanpa harus jalan operasi.
...atas bantuannya saya ucapin Thanks ya

4
Matematika / pigeonhole principle?
« pada: November 12, 2010, 02:29:28 PM »
..Mohon bantuannya untuk menjelaskan dengan mudah apa yang dimaksud dengan "pigeonhole principle" atau prinsip sarang merpati....saya membacanya dibuku2 tetapi tidak ngerti2 juga konsep dasarnya.
Barangkali ada teman2 ForSa sekalian yang mengtahui jauh mengenai ini...atas bantuannya saya ucapkan thanks :kribo:

5
Kimia / Vodka and Citrus Sodas Keep Cut Flowers Fresh
« pada: September 24, 2010, 02:00:36 PM »
 Dapat artikel copas dari forum lain, tetapi ini masih perlu diteliti lagi kebenarannya, siapa tau ada yang mau nanggepin kejadian ini atau mau ngetesnya pada bunga2 lain ... :)
Vodka and Citrus Sodas Keep Cut Flowers Fresh
Lemon-lime soda brightens those drooping bouquets and vodka gets in the way of aging

The day after Valentine's Day, flower bouquets from sweethearts around the world begin to fade. A rose's vibrant red dulls to dried-out brown, and flowers begin to droop. Some say adding a citrus-flavored soda, such as 7-Up or Sprite, or an alcohol like vodka to the vase of water will lengthen the time these flowers remain beautiful.

According to floriculturists, they are right; if the mixture of soda and water is in the correct proportion, a bouquet will remain bright, because the combination provides the flowers with the water and food they need. "The 7-Up formula works really well," says Susan Han, a professor in the plant, soil and insect science department at the University of Massachusetts Amherst. Vodka also works as a flower preservative by interfering with the plant's ripening process but it is less practical to use.

 Cut flowers, like those in a bouquet, are separated from their roots and no longer make food for themselves. Instead, their environment provides everything necessary to keep them fresh. Slightly acidic water travels up the stems to the flowers more rapidly than neutral or basic water, keeping the flowers hydrated and fresh. But in addition to water, plants need sugar for food.
This necessary combination of acidic water and sugar describes 7-Up or Sprite, says William Miller, a professor of horticulture at Cornell University. One can of either is loaded with citric acid that lowers the pH (increases the acidity) of the soda and contains about 38 grams of sugar. But, while water and sugar keep the flowers fresh, this mixture also encourages bacterial growth, which can harm the flowers. "So add bleach," Han says. A little bleach kills the bacteria without damaging the flowers.

When brewing this concoction, which is essentially what flower food packets hold, Miller and John Dole, a professor of horticulture at North Carolina State University, recommend one can of water for every can of soda added to the vase. Han, however, prefers a three-to-one ratio of water to soda, along with a few drops of bleach to kill the bacteria.

Vodka has a different effect on a bouquet of flowers: When added to a vase, it preserves them, probably by inhibiting ethylene production, Dole says. Ethylene is a ripening gas emitted by plants that helps them mature. Inhibiting this gas could slow wilting. Vodka, however, is not a very viable preservative. Plantslike many peoplecan only tolerate small concentrations of alcohol, up to eight percent, Dole explains, and 80-proof vodka from the liquor store is 40 percent alcohol. To be effective rather than harmful, the liquor would need to be dilutedInstead, growers use a more effective preservative, silver thiosulfate, which also inhibits ethylene, he says.

Other flower care strategies can help a bouquet stay beautiful. When the flowers arrive home, half an inch to an inch of the stem should be cut off. This prevents air from being sucked into the stem and creating a blockage in the plant's uptake system, Miller says. Also, removing the ends physically removes any bacteria that might be growing there, he adds. Roughly every three days another inch should be cut from the stem bottoms and the bouquet should be placed in a clean vase. "If you wouldn't drink out of your vase, don't be putting flowers in it," Dole advises. After fresh food and water are added to the clean vase, the bouquet should be placed in a bright, cool spot.

No matter what efforts are made, of course, over time the flowers will slowly die. "It is perfectly okay to go through and pluck out the dead flowers," Miller says. That way the remaining bouquet looks bright and pretty.

Sodas like 7-Up and Sprite may keep flowers from a sweetheart fresh but what keeps sweethearts fresh is not yet known to sciencethough vodka and soda might be key ingredients there, too.

sumber : http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-vodka-citrus-sodas-keep-flowers-fresh

6
Astronomi dan Kosmologi / Constellation as sign?
« pada: September 22, 2010, 08:11:00 PM »
...sebelumnya aku membaca mengenai pengertian tahun cahaya; yaitu jarak yang ditempuh cahaya dalam satu tahun dalam ruang hampa udara. Dan dibuku2 pengetahuan umum sering diberitakan bahwa jarak bintang terdekat (proxima centauri) saja sekitar lebih dari 4 tahun cahaya(dapat dilihat dengan teleskop atau mata telanjang juga sieh ::)), dengan asumsi bahwa cahaya membutuhkan waktu 4 tahun untuk mencapai tempat seperti itu, tetapi bintang itu bisa saja mengalami perjalanan atau lenyap. Misalkan bintang itu lenyap sekarang, maka butuh 4 tahun menyadari bahwa bintang itu sudah tidak ada lagi. Tetapi bagaimana orang zaman dahulu sering memetakan bintang2 dan dibuat sebagai penunjk arah bumi layaknya kompas. Contohnya rasi bintang biduk menuntukkan arah utara, bisa saja bintang biduk tidak terbentuk lagi?  ???
thanks

7
Biologi / kenapa ayam berkokok pagi hari?
« pada: September 14, 2010, 10:46:21 AM »
..kenapa ayam jantan mesti berkokok pagi hari? dan kenapa ayam betina tidak? apa ayam dapat mengerti waktu?

8
Pseudo-science dan Science-Fiction / Devil's Kettle Falls
« pada: Juli 29, 2010, 11:49:29 AM »
Devil's Kettle Falls

Kutip
Devil's Kettle Falls is in Minnesota's Judge Magney State Park. This is a very unusual, and even mysterious waterfall. As can be seen in the above picture, the river is split in two as it goes over the falls. The section on the right, lands at the base of the falls and continues downstream. The section on the left vanishes into a pothole known as the Devil's Kettle and noone knows where it goes. It is believed that the water makes its way out to Lake Superior by means of underground passages, but the exact details are unknown. They have thrown dyes and logs and other things into the pothole, but apparently nothing ever comes out. If you have ever worried about falling over a waterfall, imagine falling into the Devil's Kettle.

Finding the Falls is easy. The hike to the falls is about one mile. Along the way you will pass the Upper Falls.


Half the river vanishes into this pothole

source:
http://en.wikipedia.org/wiki/Judge_C._R._Magney_State_Park
http://gowaterfalling.com/waterfalls/devilskettle.shtml
<a href="http://www.youtube.com/v/uKhJIhA14JI&rel=0" target="_blank">http://www.youtube.com/v/uKhJIhA14JI&rel=0</a>

9
Kimia / Mekanisme obat(racun) nyamuk?
« pada: Juli 25, 2010, 06:55:10 PM »
...ngga tau mesti masuk Board mana, kalo ngga tepat bisa dipindahin kok...
Pertama, ada yang bisa jelaskan bagaimana mekanisme obat nyamuk bakar bisa bikin nyamuk mati...? apa nyamuk itu menghirup gas pembakarannya lalu mereka langsung lemas, pas diteliti aku nemuin nyamuk itu lemas dan ngga mampu mengelopakkan sayapnya(padahal nyamuknya ngga dikurung didalam obat nyamuk bakar, kok... ::))
Kedua, mana yang lebih mutahir make obat nyamuk bakar atau yang elektrik?

10
Sastra dan Budaya / siapakah paman sam itu?
« pada: Juli 21, 2010, 08:47:02 PM »
....pastinya sering dengar kalo negara Amerika sering disebut sebagai negri paman sam, jadi siapa paman sam itu?

11
Pseudo-science dan Science-Fiction / who was Fulcanelli?
« pada: Juli 07, 2010, 10:43:08 AM »
....ada yang kenal dengan Fulcanelli ngga? seorang master alchemist perancis dan penulis misterius. Menurut kabarnya Fulcanelli ini memberikan jumlah kecil dari "Proyeksi Powder" pada muridnya Eugene Canseliet dan berhasil melakukan transmutasi 100 gr timah menjadi emas di laboratorium gas karya Sarcelles...
Fulcanelli ini pun sempat diburu Nazi karena dugaan punya pengetahuan tentang senjata nuklir pada ambang perang dunia II....
  Menurut Canseliet, pertemuan terakhir dengan Fulcanelli terjadi pada tahun 1953(tahun setelah menghilang) ketika dia pergi ke spanyol dan dibawa kesebuah istana yang tinggi di pegunungan untuk bertemu dengan bekas majikannya. Canseliet menganggap Fulcanelli bagai orang tuanya berumur 80an, tetapi ternyata tidak sang master ternyata pria berusia 50an. Reuni itu terjadi singkat dan Fulcanelli kembali menghilang tanpa meninggalkan jejak...
Kutip
Fulcanelli is almost certainly a pseudonym  assumed, in the early XXth century, by a French alchemist  and esoteric author, whose identity is still debated.[1]  The name Fulcanelli seems to be a play on words: Vulcan the ancient Roman god of fire plus El, a Canaanite name for God and so the Sacred Fire.[2]  He is also called the Master Alchemist. The appeal of Fulcanelli as a cultural phenomenon is partly due to the mystery that surrounds most aspects of his life and works; one of the anecdotes pertaining to his life retells, in particular, how his most devoted pupil Eugène Canseliet performed a successful transmutation  of 100 grams of lead into gold in a laboratory of the gas works of Sarcelles at the Georgi company with the use of a small quantity of the "Projection Powder" given to him by his teacher, in the presence of Julien Champagne and Gaston Sauvage.
Fulcanelli was undoubtedly a Frenchman, widely and profoundly educated, and learned in the ways of alchemical lore, architecture, art, science, and languages. Fulcanelli wrote two books that were published after his disappearance in 1926, having left his magnum opus with his only student, Eugène Canseliet. Le Mystere des Cathedrales first edition consisted of 300 copies and was published by Jean Schemit at 52 Rue Laffitte, Paris, France.[3]

Theories about Fulcanelli speculate that he was one or another famous French occultist of the time: perhaps a member of the former Royal Family (the Valois), or another member of the Frères d'Heliopolis (Brotherhood of Heliopolis, a society centred around Fulcanelli which included Eugène Canseliet, Jean-Julien Champagne and Jules Boucher). Canseliet's only student, Patrick Rivière, believes that Fulcanelli's true identity was Jules Violle, famous French physicist.[4] In a 1996 book, samples of writing by Jean-Julien Hubert Champagne (born January 23, 1877) and Fulcanelli are compared, and show considerable similarity.[5] In any event, by 1916, Fulcanelli had accepted Canseliet, who was then only sixteen, as his first student. In 1921, he accepted the sons of Ferdinand de Leseps as students and in 1922, two more students, Jules Boucher and Gaston Sauvage. In 1925, Fulcanelli moved to 59 rue Rochechouart where he allegedly was successful in transmuting base metals into gold.[6]

In the book Beyond Painting, published in 1936, surrealist Max Ernst hints at the existence of Fulcanelli as many surrealist painters were influenced by Alchemical lore but then, even the great American occult historian Manly Palmer Hall fails to mention the Master Alchemist.[7]

In 1960, with the publication of the international bestseller The Morning of the Magicians, Pauwels and Bergier brought the mystery of the Master Alchemist into the limelight of the public eye.[8]

Fulcanelli's Master

Without overlooking the belief of some researchers that Canseliet himself could have been Fulcanelli, Canseliet believed Fulcanelli's Master was Basil Valentine, the theoretical Master in any case, for Fulcanelli's true initiator was his own wife. As Fulcanelli describes in a strange letter he practically kept as a talisman about the completion of the Great Work by someone who is presumably Basil Valentine, he also mentions his own wife: "...When my wife told me the good news" and "...my wife, with the inexplicable intuition of sensitives, had a really strange dream." In other words, when referring to something as important as the Great Work, he mentions his wife as someone important to the Magnum Opus.[9] [10] Canseliet points out the mistake made by the Abbé Villain spelling Flamel's wife's name as "Pernelle". Nicolas Flamel himself knows her as "Perrenelle" or the eternal almighty Lady of the Great Work, Mother Nature herself. According to Canseliet, she is "... La Dame par excellence."[11]

Nazi interest in Alchemy

In the 1920s Franz Tausend, the German alchemist, was involved in a gold-making project at the same time as General Erich von Ludendorff was involved in the same project presumably to help finance the Nazi Party. [12].

It is believed that on the verge of World War II, the Abwehr was in active (but fruitless) pursuit of Fulcanelli because of his alleged knowledge of the technology of nuclear weapons.

Conclusion

According to Louis Pauwels, Fulcanelli survived World War II and disappeared completely after the Liberation of Paris. Every attempt to find him failed. In August 1945, G-2 Army Intelligence asked Bergier to contact a certain Army major who was in charge of the operation of searching and discovering German research reports on atomic energy. The anonymous U. S. Army major wanted to know the whereabouts of Fulcanelli. Bergier could not say and the army major seemed satisfied Fulcanelli could not be found.[13]

Alchemy in modern times

In 1980, Glenn Seaborg transmuted several thousand atoms of bismuth into gold at the Lawrence Berkeley Laboratory. His experimental technique, using nuclear physics, was able to remove protons and neutrons from the bismuth atoms. Seaborg's technique would have been far too expensive to enable routine manufacturing of gold, but his work is the closest achievement, so far, to the mythical Philosopher's Stone of the ancient Alchemists. Alchemy is very much alive today. [14]

Kutip
Rendez-vous à Paris

Walter Lang reports that Fulcanelli contacted Jacques Bergier (Яков Михайлович Бергёр) to warn French atomic physicist André Hellbronner of man's impending use of nuclear weapons. According to Fulcanelli, nuclear weapons had been used before against humanity, being the Abyss pandemonium as noted much later by Dr. Albert Einstein on the front page of the New York Post after the detonation of the first Hydrogen bomb in the early 50s (October 31, 1952). Dr. Hellbronner and Chevillon among others were assassinated by the Gestapo towards the end of World War II.[15]

The meeting between Jacques Bergier and Fulcanelli took place in June 1937 in a laboratory of the Gas Board in Paris. According to Neil Powell, the following is a translation of the original verbatim transcript of the rendezvous. Fulcanelli told Bergier:

"You're on the brink of success, as indeed are several other of our scientists today. Please, allow me, be very very careful. I warn you... The liberation of nuclear power is easier than you think and the radioactivity artificially produced can poison the atmosphere of our planet in a very short time, a few years. Moreover, atomic explosives can be produced from a few grains of metal powerful enough to destroy whole cities. I'm telling you this for a fact: the alchemists have known it for a very long time... "I shall not attempt to prove to you what I'm now going to say but I ask you to repeat it to M. Hellbronner: certain geometrical arrangements of highly purified materials are enough to release atomic forces without having recourse to either electricity or vacuum techniques... The secret of alchemy is this: there is a way of manipulating matter and energy so as to produce what modern scientists call 'a field of force'. The field acts on the observer and puts him in a privileged position vis-à-vis the Universe. From this position he has access to the realities which are ordinarily hidden from us by time and space, matter and energy. This is what we call the Great Work." [16]

When Bergier asked Fulcanelli about the Philosopher's Stone, the alchemist answered: "...the vital thing is not the transmutation of metals but that of the experimenter himself. It is an ancient secret that a few people rediscover each century. Unfortunately, only a handful are successful..."[17]

Aftermath

In December 1938, the German chemists Otto Hahn and Fritz Strassmann sent a manuscript to Naturwissenschaften reporting they had detected the element barium after bombarding uranium with neutrons.[18] Lise Meitner and her nephew Otto Robert Frisch correctly interpreted these results as being nuclear fission.[19]

...More http://en.wikipedia.org/wiki/Fulcanelli

12
Sastra dan Budaya / menggambar manga
« pada: Juli 03, 2010, 09:17:53 PM »
..berhubung di board ini termasuk seni, maka aku mau minta berbagi teman2 forsa yang hobi nggambar, terutama menggambar manga...ada yang tau teknik menggambar manga? sewaktu kecil2 dulu aku juga sering bikin komik dari G-Pen, dulunya sih pengen juga jadi seorang mangaka, taunya jadi kek gini...tetapi hobi masih jalan kok...bagi yang sudah master dalam nggambar manga bisa share ilmunya dong...salah satu kesulitanku adalah alat tulis, banyak gambarnya ngga bagus kalo cuma pake G-pen ada yang tau alat apa aja yang dibutuhin untuk menggambarnya?

13
Astronomi dan Kosmologi / ekor komet membelakangi matahari
« pada: Juni 27, 2010, 07:22:17 PM »
...ada yang tau kenapa ekor komet selalu membelakangi matahari?

14
Kotak Saran / icon smiley
« pada: Juni 26, 2010, 11:17:46 AM »
...aku ngusul buat bikin icon smiley yang lebih keren dan lebih banyak, dong....
kadang ada ungkapan yang pengen dituliskan dengan smiley yang ngga bisa terungkap biasa...biar diskusinya ngga tambah tegang aja :)

15
Kimia / listrik masa depan dari bakteri?
« pada: Juni 26, 2010, 11:10:47 AM »
ini artikel yang pernah dibikin Oleh Tomi Rustamiaji, S.Si dari Institut Teknologi Bandung
Bakteri : Masa Depan Listrik?


    Sel bahan bakar dengan tenaga bakteri kini merupakan salah satu jalan yang menjanjikan untuk menghasilkan energi dari limbah biologis. Namun perlu dicatat, ini dapat terjadi hanya jika kita dapat menangkap potensial elektrik mikroba dengan efisien.

Kimiawan di Singapura dan Jepang telah memeriksa dua pendekatan berbeda untuk meningkatkan interfase antara bakteri dan elektroda dalam sel bahn bakar mikrobial. Alat ini menggunakan mikroorganisme untuk menghancurkan molekul organik dengan oksidasi, dimana proses ini menghasilkan elektron. Menangkap elektron-elektron ini pada anoda sel bahan bakar ialah kunci untuk memanen sumber energi ini.
    Masanori Adachi dan rekan sejawat di Ebara Research, Fujisawa-shi Jepang, telah meningkatkan interfase anode dengan menginkorporasikan sebuah mediator polimer ke permukaan anoda. Permukaan polimer berbasis antrakuinon ini direduksi secara elektrokimia oleh elektron yang dihasilkan oleh penghancuran ‘bahan bakar’ asetat oleh bakteri. Lapisan polimer melewatkan elektron-elektron ini hingga ke anoda, dan kemudian prosesnya berulang kembali.

Bakteri melepaskan sebuah mediator hidrokuinon
yang teroksidasi pada elektroda dan menjadi kuinon.

Tim Ebara menguji sistem anoda terselbubung ini selama lebih dari empat bulan. Hasilnya tidak ditemukan adanya penurunan performa pada rentang waktu tersebut. Performa stabil ini mengindikasikan sebuah sel bahan bakar mikroba komersial yang siap digunakan unttuk masyarakat luas.

Dalam sebuah studi yang terpisah, Chang Ming Li dan rekan sejawat di Nanyang Technological University, Singapura telah mengembangkan sebuah sel bahan bakar dimana bakteri mentransferkan elektron kepada anoda dengan sendirinya. Studi sebelumnya tentang Escheria *piip* yang ditumbuhkan dibawah kondisi elektrokimia ditemukan bahwa bakteri ini menjadi memiliki kemampuan untuk mentransferkan elektron ke elektroda. Li menemukan pula bahwa sel-sel mengekskresikan mediator alami, sebuah struktur berbasis hidrokuinon yang memiliki fungsi serupa dengan polimer Adachi.

Li dan timnya mengemukakan bahwa bakteri mungkin berevolusi untuk mengembangkan pori diluar membran luar mereka, yang membuat hidrokuinon mampu untuk meninggalkan sel dan mencapai elektroda. “Sel bahan bakar mikrobial tanpa mediator sangatlah menarik karena keuntungan dari segi efisiensi tinggi konversi energi dan biaya pembuatan yang rendah” ujar Li. Tantangan berikutnya adalah untuk melakukan rekayasa genetik strain bakteri yang menghasilkan senyawa mediator yang lebih banyak.

“Kedua studi ini menunjukkan kemajuan baik menuju pengembangan sel bahan bakar mikrobial” ungkap Xiao Guo, seorang peneliti sel bahan bakar biokimia di University College London, Inggris. “Namun kita masih memerlukan peningkatan dari kerapatan energi dengan orde dua atau tiga kali lipat untuk mewujudkan sel bahan bakar praktis. Interfase biologis adalah jawabannya. Jika kita mampu merekayasa sebuah sistem yang menghubungkan langsung situs transfer elektron ke elektroda, kita dapat meningkatkan rapat energi dengan signifkan” tambahnya.

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