saco-indonesia.com, Petir adalah peristiwa alam yang sering terjadi di bumi, terjadinya seringkali mengikuti peristiwa hujan baik air atau es, peristiwa ini telah dimulai dengan munculnya awan hitam dan lidah api listrik bercahaya terang yang bergerak merambat terus memanjang kearah bumi bagaikan sulur akar dan kemudian diikuti oleh suara menggelegar dan efeknya juga akan sangat fatal bila mengenai mahluk hidup.
PROSES TERJADINYA PETIR
Terdapat 2 teori yang mendasari proses terjadinya petir :
Proses Gesekan antar awan
a. Proses Ionisasi
Petir telah terjadi diakibatkan oleh terkumpulnya ion bebas bermuatan negatif dan positif di awan, ion listrik dihasilkan oleh gesekan antar awan dan kejadian Ionisasi ini telah disebabkan oleh perubahan bentuk air mulai dari cair menjadi gas atau sebaliknya, bahkan perubahan padat (es) telah menjadi cair dan pada tahap pembekuan ini mencapai suhu dibawah 0 derajat yaitu antara -10 sampai -14 derajad celcius
Ion bebas telah menempati permukaan awan dan bergerak mengikuti angin berhembus, bila awan-awan telah terkumpul di suatu tempat maka awan bermuatan akan memiliki beda potensial cukup besar untuk dapat menyambar permukaan bumi maka inilah yang disebut petir.
b. Gesekan antar awan
Pada awalnya awan akan bergerak mengikuti arah angin, selama proses bergeraknya awan ini maka akan saling bergesekan satu dengan yang lainnya , dari proses ini terlahir electron-electron bebas bermutan negatif yang telah memenuhi permukaan awan. proses ini bisa digambarkan secara sederhana pada sebuah penggaris plastik yang digosokkan pada rambut maka penggaris ini akan mampu menarik potongan kertas.
Pada suatu saat awan ini akan terkumpul di sebuah kawasan, saat inilah petir dimungkinkan telah terjadi karena electron-elektron bebas ini telah saling menguatkan satu dengan lainnya. Sehingga telah memiliki cukup beda potensial untuk dapat menyambar permukaan bumi. kedua teori ini mungkin juga masuk akal meski kejadian sebenarnya masih merupakan sebuah misteri.
PERLINDUNGAN TERHADAP BAHAYA PETIR
Manusia selalu mencoba untuk dapat menjinakkan keganasan alam,atau setidaknya menghidarinya, salah satunya adalah Sambaran Petir. dan metode yang pernah dikembangkan:
1. Penangkal Petir Kovensional / Faraday / Frangklin
Kedua ilmuan diatas Faraday dan Frangklin telah mengetengahkan system yang hampir sama , yakni system penyalur arus listrik dengan menghubungkan antara bagian atas bangunan dan grounding. Sedangkan system perlindungan yang telah dihasilkan ujung penerima / Splitzer adalah sama pada rentang 30 ~ 45 ‘ . Perbedaannya adalah system yang telah dikembangkan oleh Faraday bahwa Kabel penghantar terletak pada sisi luar bangunan dengan pertimbangan bahwa kabel penghantar juga berfungsi sebagai penerima sambaran, dan bentuknya Berupa sangkar elektris atau biasa disebut sangkar Faraday.
2. Penangkal Petir Radio Aktif
Penelitian terus terus berkembang dan dihasilkan kesimpulan bahwa petir telah terjadi karena ada muatan listrik di awan dihasilkan oleh proses ionisasi , maka penggagalan proses ionisasi di lakukan dengan cara memakai Zat beradiasi misl. Radiun 226 dan Ameresium 241 , karena 2 bahan ini juga mampu menghamburkan ion radiasinya yang bisa menetralkan muatan listrik awan.
Sedang manfaat lain adalah hamburan ion radiasi akan dapat menambah muatan pada Ujung Finial / Splitzer dan bila mana awan yang bermuatan besar tidak mampu di netralkan oleh zat radiasi kemudian menyambar, maka akan condong mengenai unit radiasi ini .
Keberadaan penangkal petir jenis ini juga sudah dilarang pemakaiannya , berdasarkan kesepakatan internasional dengan pertimbangan mengurangi pemakaian zat beradiasi dimasyarakat yang disinyalir mempunyai efek negatif pada lingkungan hidup dan kesehatan.
3. Penangkal Petir Elektrostatic
Prinsip kerja penangkal petir Elektrostatik adalah dengan mengadopsi sebagian system penangkal petir Radioaktif , yakni dengan menambah muatan pada ujung finial / splitzer agar petir selalu memilih ujung ini untuk disambar .
Perbedaan dari sisten Radioaktif dan Elektrostatik ada pada energi yang dipakai. Untuk Penangkal Petir Radioaktif muatan listrik dihasilkan dari proses hamburan zat beradiasi sedangkan pada penangkal petir elektrostatik energi listrik dihasilkan dari Listrik Awan yang menginduksi permukaan bumi.
CARA KERJA PENANGKAL PETIR NEOFLASH
Ketika awan bermuatan listrik telah melintas diatas sebuah bangunan yang terpasang penangkal petir neoFlash, maka elektroda penerima pada bagian samping NeoFLASH ini dapat mengumpulkan dan menyimpan energi listrik awan pada unit kapasitornya . Setelah energi ini cukup besar maka dilepas dan diperbesar beda potensialnya pada bagian Ion Generator.
Pelepasan muatan listrik pada unit Ion Generator ini di picu oleh sambaran, yakni ketika lidah api menyambar permukaan bumi maka semua muatan listrik di bagian ion generator dilepaskan keudara melalui Central Pick Up agar menimbulkan lidah api penuntun keatas ( Streamer leader ) untuk dapat menyambut sambaran petir yang terjadi kemudian menuntunya masuk kedalam satu titik sambar yang terdapat unit Neoflash ini.
Pada unit Penangkal Petir NEOFLASH secara simultan bekerja bergantian dari masing-masing unit penerima induksi , jumlahnya tergantung dari tipe dan modelnya. Bekerjanya secara bergantian dimana bila salah satu bagian unit melepaskan muatan ke udara / streamer maka ada bagian lain yang dalam proses pengisian muatan awan.
Tentu akurasi dan kemampuan Penangkal Petir NeoFlash masih tergantung dari 2 hal pendukung instalasi, yaitu:
1. Kabel Penghantar harus minimal 50 mm
2. Grounding maksimal 5 Ohm
Bila 2 syarat pendukung ini juga sudah terpenuhi maka kemampuan penangkal petir neoflash akan maksimal.
ISTILAH PENANGKAL PETIR & ANTI PETIR
Penangkal Petir dan Anti Petir mungkin itu adalah istilah yang sudah salah kaprah dalam bahasa kita, kesan yang ditimbulkan dua istilah ini adalah aman 100 % terhadap petir, akan tetapi kejadiannya tidak demikian.
Dalam penanganan bahaya petir memang ada beberapa faktor yang sangat mempengaruhi, bilamana kita ingin solusi/penyelesaian total akan bahaya petir, kita harus melihat faktor faktor tersebut.
Sambaran Tidak langsung pada bangunan yakni ketika sambaran mengenai obyek diluar areal perlindungan dari penangkal petir yang terpasang , kemudian arus petir ini akan merambat melalui instalasi listrik , kabel data atau apa saja mengarah ke bangunan. Akhirnya hentakan tegangan dan arus merusak unit peralatan listrik / elektronik kita.
Masalah ini juga semakin runyam disaat ini karena banyak peralatan elektronik dengan menggunakan tegangan kerja kecil , DC , dan sensitif, Khususnya di urusan data transfer.
Maka pada dasarnya pengaman sambaran petir langsung / Eksternal penangkal petir bukan membuat posisi kita aman 100 % terhadap petir, akan tetapi membuat posisi bangunan kita terhindar dari kerusakan fatal akibat sambaran Langsung, serta meminimalisir efek kerusakan pada peralatan elektronik bila ada sambaran menyambar bangunan kita.
mungkin Penyalur Arus Petir adalah istilah tepatnya.
Masih ada kemungkinan lain yakni sambaran petir tidak langsung , yakni sambaran yang pada dasarnya tidak mengenai lokasi bangunan tetapi mengenai jauh diluar lokasi tetapi lonjakan listriknya merambat masuk ke jaringan instalasi listrik di bangunan dan merusak peralatan elektronik, Untuk penanganan sambaran petir tidak langsung dapat digunakan Arrester yakni perangkat yang bisa memotong dan membelokkan lonjakan arus / tegangan petir ke dalam grounding .
THE WRITERS ASHLEY AND JAQUAVIS COLEMAN know the value of a good curtain-raiser. The couple have co-authored dozens of novels, and they like to start them with a bang: a headlong action sequence, a blast of violence or sex that rocks readers back on their heels. But the Colemans concede they would be hard-pressed to dream up anything more gripping than their own real-life opening scene.
In the summer of 2001, JaQuavis Coleman was a 16-year-old foster child in Flint, Mich., the former auto-manufacturing mecca that had devolved, in the wake of General Motors’ plant closures, into one of the country’s most dangerous cities, with a decimated economy and a violent crime rate more than three times the national average. When JaQuavis was 8, social services had removed him from his mother’s home. He spent years bouncing between foster families. At 16, JaQuavis was also a businessman: a crack dealer with a network of street-corner peddlers in his employ.
One day that summer, JaQuavis met a fellow dealer in a parking lot on Flint’s west side. He was there to make a bulk sale of a quarter-brick, or “nine-piece” — a nine-ounce parcel of cocaine, with a street value of about $11,000. In the middle of the transaction, JaQuavis heard the telltale chirp of a walkie-talkie. His customer, he now realized, was an undercover policeman. JaQuavis jumped into his car and spun out onto the road, with two unmarked police cars in pursuit. He didn’t want to get into a high-speed chase, so he whipped his car into a church parking lot and made a run for it, darting into an alleyway behind a row of small houses, where he tossed the quarter-brick into some bushes. When JaQuavis reached the small residential street on the other side of the houses, he was greeted by the police, who handcuffed him and went to search behind the houses where, they told him, they were certain he had ditched the drugs. JaQuavis had been dealing since he was 12, had amassed more than $100,000 and had never been arrested. Now, he thought: It’s over.
But when the police looked in the bushes, they couldn’t find any cocaine. They interrogated JaQuavis, who denied having ever possessed or sold drugs. They combed the backyard alley some more. After an hour of fruitless efforts, the police were forced to unlock the handcuffs and release their suspect.
JaQuavis was baffled by the turn of events until the next day, when he received a phone call. The previous afternoon, a 15-year-old girl had been sitting in her home on the west side of Flint when she heard sirens. She looked out of the window of her bedroom, and watched a young man throw a package in the bushes behind her house. She recognized him. He was a high school classmate — a handsome, charismatic boy whom she had admired from afar. The girl crept outside and grabbed the bundle, which she hid in her basement. “I have something that belongs to you,” Ashley Snell told JaQuavis Coleman when she reached him by phone. “You wanna come over here and pick it up?”
In the Colemans’ first novel, “Dirty Money” (2005), they told a version of this story. The outline was the same: the drug deal gone bad, the dope chucked in the bushes, the fateful phone call. To the extent that the authors took poetic license, it was to tone down the meet-cute improbability of the true-life events. In “Dirty Money,” the girl, Anari, and the crack dealer, Maurice, circle each other warily for a year or so before coupling up. But the facts of Ashley and JaQuavis’s romance outstripped pulp fiction. They fell in love more or less at first sight, moved into their own apartment while still in high school and were married in 2008. “We were together from the day we met,” Ashley says. “I don’t think we’ve spent more than a week apart in total over the past 14 years.”
That partnership turned out to be creative and entrepreneurial as well as romantic. Over the past decade, the Colemans have published nearly 50 books, sometimes as solo writers, sometimes under pseudonyms, but usually as collaborators with a byline that has become a trusted brand: “Ashley & JaQuavis.” They are marquee stars of urban fiction, or street lit, a genre whose inner-city settings and lurid mix of crime, sex and sensationalism have earned it comparisons to gangsta rap. The emergence of street lit is one of the big stories in recent American publishing, a juggernaut that has generated huge sales by catering to a readership — young, black and, for the most part, female — that historically has been ill-served by the book business. But the genre is also widely maligned. Street lit is subject to a kind of triple snobbery: scorned by literati who look down on genre fiction generally, ignored by a white publishing establishment that remains largely indifferent to black books and disparaged by African-American intellectuals for poor writing, coarse values and trafficking in racial stereotypes.
But if a certain kind of cultural prestige is shut off to the Colemans, they have reaped other rewards. They’ve built a large and loyal fan base, which gobbles up the new Ashley & JaQuavis titles that arrive every few months. Many of those books are sold at street-corner stands and other off-the-grid venues in African-American neighborhoods, a literary gray market that doesn’t register a blip on best-seller tallies. Yet the Colemans’ most popular series now regularly crack the trade fiction best-seller lists of The New York Times and Publishers Weekly. For years, the pair had no literary agent; they sold hundreds of thousands of books without banking a penny in royalties. Still, they have earned millions of dollars, almost exclusively from cash-for-manuscript deals negotiated directly with independent publishing houses. In short, though little known outside of the world of urban fiction, the Colemans are one of America’s most successful literary couples, a distinction they’ve achieved, they insist, because of their work’s gritty authenticity and their devotion to a primal literary virtue: the power of the ripping yarn.
“When you read our books, you’re gonna realize: ‘Ashley & JaQuavis are storytellers,’ ” says Ashley. “Our tales will get your heart pounding.”
THE COLEMANS’ HOME BASE — the cottage from which they operate their cottage industry — is a spacious four-bedroom house in a genteel suburb about 35 miles north of downtown Detroit. The house is plush, but when I visited this past winter, it was sparsely appointed. The couple had just recently moved in, and had only had time to fully furnish the bedroom of their 4-year-old son, Quaye.
In conversation, Ashley and JaQuavis exude both modesty and bravado: gratitude for their good fortune and bootstrappers’ pride in having made their own luck. They talk a lot about their time in the trenches, the years they spent as a drug dealer and “ride-or-die girl” tandem. In Flint they learned to “grind hard.” Writing, they say, is merely a more elevated kind of grind.
“Instead of hitting the block like we used to, we hit the laptops,” says Ashley. “I know what every word is worth. So while I’m writing, I’m like: ‘Okay, there’s a hundred dollars. There’s a thousand dollars. There’s five thousand dollars.’ ”
They maintain a rigorous regimen. They each try to write 5,000 words per day, five days a week. The writers stagger their shifts: JaQuavis goes to bed at 7 p.m. and wakes up early, around 3 or 4 in the morning, to work while his wife and child sleep. Ashley writes during the day, often in libraries or at Starbucks.
They divide the labor in other ways. Chapters are divvied up more or less equally, with tasks assigned according to individual strengths. (JaQuavis typically handles character development. Ashley loves writing murder scenes.) The results are stitched together, with no editorial interference from one author in the other’s text. The real work, they contend, is the brainstorming. The Colemans spend weeks mapping out their plot-driven books — long conversations that turn into elaborate diagrams on dry-erase boards. “JaQuavis and I are so close, it makes the process real easy,” says Ashley. “Sometimes when I’m thinking of something, a plot point, he’ll say it out loud, and I’m like: ‘Wait — did I say that?’ ”
Their collaboration developed by accident, and on the fly. Both were bookish teenagers. Ashley read lots of Judy Blume and John Grisham; JaQuavis liked Shakespeare, Richard Wright and “Atlas Shrugged.” (Their first official date was at a Borders bookstore, where Ashley bought “The Coldest Winter Ever,” the Sister Souljah novel often credited with kick-starting the contemporary street-lit movement.) In 2003, Ashley, then 17, was forced to terminate an ectopic pregnancy. She was bedridden for three weeks, and to provide distraction and boost her spirits, JaQuavis challenged his girlfriend to a writing contest. “She just wasn’t talking. She was laying in bed. I said, ‘You know what? I bet you I could write a better book than you.’ My wife is real competitive. So I said, ‘Yo, all right, $500 bet.’ And I saw her eyes spark, like, ‘What?! You can’t write no better book than me!’ So I wrote about three chapters. She wrote about three chapters. Two days later, we switched.”
The result, hammered out in a few days, would become “Dirty Money.” Two years later, when Ashley and JaQuavis were students at Ferris State University in Western Michigan, they sold the manuscript to Urban Books, a street-lit imprint founded by the best-selling author Carl Weber. At the time, JaQuavis was still making his living selling drugs. When Ashley got the phone call informing her that their book had been bought, she assumed they’d hit it big, and flushed more than $10,000 worth of cocaine down the toilet. Their advance was a mere $4,000.
Those advances would soon increase, eventually reaching five and six figures. The Colemans built their career, JaQuavis says, in a manner that made sense to him as a veteran dope peddler: by flooding the street with product. From the start, they were prolific, churning out books at a rate of four or five a year. Their novels made their way into stores; the now-defunct chain Waldenbooks, which had stores in urban areas typically bypassed by booksellers, was a major engine of the street-lit market. But Ashley and JaQuavis took advantage of distribution channels established by pioneering urban fiction authors such as Teri Woods and Vickie Stringer, and a network of street-corner tables, magazine stands, corner shops and bodegas. Like rappers who establish their bona fides with gray-market mixtapes, street-lit authors use this system to circumnavigate industry gatekeepers, bringing their work straight to the genre’s core readership. But urban fiction has other aficionados, in less likely places. “Our books are so popular in the prison system,” JaQuavis says. “We’re banned in certain penitentiaries. Inmates fight over the books — there are incidents, you know? I have loved ones in jail, and they’re like: ‘Yo, your books can’t come in here. It’s against the rules.’ ”
The appeal of the Colemans’ work is not hard to fathom. The books are formulaic and taut; they deliver the expected goods efficiently and exuberantly. The titles telegraph the contents: “Diary of a Street Diva,” “Kiss Kiss, Bang Bang,” “Murderville.” The novels serve up a stream of explicit sex and violence in a slangy, tangy, profane voice. In Ashley & JaQuavis’s books people don’t get killed: they get “popped,” “laid out,” get their “cap twisted back.” The smut is constant, with emphasis on the earthy, sticky, olfactory particulars. Romance novel clichés — shuddering orgasms, heroic carnal feats, superlative sexual skill sets — are rendered in the Colemans’ punchy patois.
Subtlety, in other words, isn’t Ashley & JaQuavis’s forte. But their books do have a grainy specificity. In “The Cartel” (2008), the first novel in the Colemans’ best-selling saga of a Miami drug syndicate, they catch the sights and smells of a crack workshop in a housing project: the nostril-stinging scent of cocaine and baking soda bubbling on stovetops; the teams of women, stripped naked except for hospital masks so they can’t pilfer the merchandise, “cutting up the cooked coke on the round wood table.” The subject matter is dark, but the Colemans’ tone is not quite noir. Even in the grimmest scenes, the mood is high-spirited, with the writers palpably relishing the lewd and gory details: the bodies writhing in boudoirs and crumpling under volleys of bullets, the geysers of blood and other bodily fluids.
The luridness of street lit has made it a flashpoint, inciting controversy reminiscent of the hip-hop culture wars of the 1980s and ’90s. But the street-lit debate touches deeper historical roots, reviving decades-old arguments in black literary circles about the mandate to uplift the race and present wholesome images of African-Americans. In 1928, W. E. B. Du Bois slammed the “licentiousness” of “Home to Harlem,” Claude McKay’s rollicking novel of Harlem nightlife. McKay’s book, Du Bois wrote, “for the most part nauseates me, and after the dirtier parts of its filth I feel distinctly like taking a bath.” Similar sentiments have greeted 21st-century street lit. In a 2006 New York Times Op-Ed essay, the journalist and author Nick Chiles decried “the sexualization and degradation of black fiction.” African-American bookstores, Chiles complained, are “overrun with novels that . . . appeal exclusively to our most prurient natures — as if these nasty books were pairing off back in the stockrooms like little paperback rabbits and churning out even more graphic offspring that make Ralph Ellison books cringe into a dusty corner.”
Copulating paperbacks aside, it’s clear that the street-lit debate is about more than literature, touching on questions of paternalism versus populism, and on middle-class anxieties about the black underclass. “It’s part and parcel of black elites’ efforts to define not only a literary tradition, but a racial politics,” said Kinohi Nishikawa, an assistant professor of English and African-American Studies at Princeton University. “There has always been a sense that because African-Americans’ opportunities to represent themselves are so limited in the first place, any hint of criminality or salaciousness would necessarily be a knock on the entire racial politics. One of the pressing debates about African-American literature today is: If we can’t include writers like Ashley & JaQuavis, to what extent is the foundation of our thinking about black literature faulty? Is it just a literature for elites? Or can it be inclusive, bringing urban fiction under the purview of our umbrella term ‘African-American literature’?”
Defenders of street lit note that the genre has a pedigree: a tradition of black pulp fiction that stretches from Chester Himes, the midcentury author of hardboiled Harlem detective stories, to the 1960s and ’70s “ghetto fiction” of Iceberg Slim and Donald Goines, to the current wave of urban fiction authors. Others argue for street lit as a social good, noting that it attracts a large audience that might otherwise never read at all. Scholars like Nishikawa link street lit to recent studies showing increased reading among African-Americans. A 2014 Pew Research Center report found that a greater percentage of black Americans are book readers than whites or Latinos.
For their part, the Colemans place their work in the broader black literary tradition. “You have Maya Angelou, Alice Walker, James Baldwin — all of these traditional black writers, who wrote about the struggles of racism, injustice, inequality,” says Ashley. “We’re writing about the struggle as it happens now. It’s just a different struggle. I’m telling my story. I’m telling the struggle of a black girl from Flint, Michigan, who grew up on welfare.”
Perhaps there is a high-minded case to be made for street lit. But the virtues of Ashley & JaQuavis’s work are more basic. Their novels do lack literary polish. The writing is not graceful; there are passages of clunky exposition and sex scenes that induce guffaws and eye rolls. But the pleasure quotient is high. The books flaunt a garish brand of feminism, with women characters cast not just as vixens, but also as gangsters — cold-blooded killers, “murder mamas.” The stories are exceptionally well-plotted. “The Cartel” opens by introducing its hero, the crime boss Carter Diamond; on page 9, a gunshot spatters Diamond’s brain across the interior of a police cruiser. The book then flashes back seven years and begins to hurtle forward again — a bullet train, whizzing readers through shifting alliances, romantic entanglements and betrayals, kidnappings, shootouts with Haitian and Dominican gangsters, and a cliffhanger closing scene that leaves the novel’s heroine tied to a chair in a basement, gruesomely tortured to the edge of death. Ashley & JaQuavis’s books are not Ralph Ellison, certainly, but they build up quite a head of steam. They move.
The Colemans are moving themselves these days. They recently signed a deal with St. Martin’s Press, which will bring out the next installment in the “Cartel” series as well as new solo series by both writers. The St. Martin’s deal is both lucrative and legitimizing — a validation of Ashley and JaQuavis’s work by one of publishing’s most venerable houses. The Colemans’ ambitions have grown, as well. A recent trilogy, “Murderville,” tackles human trafficking and the blood-diamond industry in West Africa, with storylines that sweep from Sierra Leone to Mexico to Los Angeles. Increasingly, Ashley & JaQuavis are leaning on research — traveling to far-flung settings and hitting the books in the libraries — and spending less time mining their own rough-and-tumble past.
But Flint remains a source of inspiration. One evening not long ago, JaQuavis led me on a tour of his hometown: a popular roadside bar; the parking lot where he met the undercover cop for the ill-fated drug deal; Ashley’s old house, the site of his almost-arrest. He took me to a ramshackle vehicle repair shop on Flint’s west side, where he worked as a kid, washing cars. He showed me a bathroom at the rear of the garage, where, at age 12, he sneaked away to inspect the first “boulder” of crack that he ever sold. A spray-painted sign on the garage wall, which JaQuavis remembered from his time at the car wash, offered words of warning:
WHAT EVERY YOUNG MAN SHOULD KNOW
ABOUT USING A GUN:
MURDER . . . 30 Years
ARMED ROBBERY . . . 15 Years
ASSAULT . . . 15 Years
RAPE . . . 20 Years
POSSESSION . . . 5 Years
JACKING . . . 20 YEARS
“We still love Flint, Michigan,” JaQuavis says. “It’s so seedy, so treacherous. But there’s some heart in this city. This is where it all started, selling books out the box. In the days when we would get those little $40,000 advances, they’d send us a couple boxes of books for free. We would hit the streets to sell our books, right out of the car trunk. It was a hustle. It still is.”
One old neighborhood asset that the Colemans have not shaken off is swagger. “My wife is the best female writer in the game,” JaQuavis told me. “I believe I’m the best male writer in the game. I’m sleeping next to the best writer in the world. And she’s doing the same.”