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NaOH 50wt% / H2S -> NaSH 30wt% -> 폐수중의 중금속 제거제,유기합성 화학 원료 및 환원제
대한민국 울산광역시 울주군 온산읍 석당길 8
| Est Items | Test Method | Specification | Typical Value |
|---|---|---|---|
| Appearance | Visual | Clear with No Particulate Matter | Clear with No Particulate Matter |
| Color APHA | ASTM D-1209 | ≤ 10 | 5 |
| Mercaptan Sulfur(wt%) | UOP-163 | ≥ 15.6 | 16.1 |
| n-Octyl Mercaptan(wt%), VPC | GC | ≥ 98.5 | 98.9 |
| Distillation range, ℃ | ASTM D-1078 | ||
| IBP, ℃ | ASTM D-1078 | ≥ 274 | 275 |
| 95% BP, ℃ | ASTM D-1078 | ≤ 278 | 276 |
| Specific Gravity @15.5/15.5 ℃ | ASTM D-4052 | 0.85 | |
| sec-Octyl Mercaptan, wt% | GC | ≤ 1.5 | 0.6 |
| Flash Point, ℃ | ASTM D-56 | 257 |




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kerosene -> NP -> Light NP -> LAB -> LAS -> 세탁용 분말세제 및 액체세제
kerosene -> NP -> Light NP -> Benzene / Propylene Tetramer -> Heavy LAB -> 윤활유,산업용 윤활기
kerosene -> NP -> Light NP -> Benzene / Propylene Tetramer -> BAB -> DBSA -> 공엽용 세척제 / PVC 2차 가소제,농약유화재
kerosene -> NP -> Light NP -> Benzene / Propylene Tetramer -> Heavy BAB -> 냉동기유,윤활제 첨가제
kerosene -> NP -> Light NP -> Benzene / Propylene Tetramer -> TAB - 청색유기안료 -> 인쇄잉크,도료,섬유,고무,플라스틱
kerosene -> NP -> Light NP -> Parasol -> 인쇄잉크,에어로졸,금속세정제
kerosene -> NP -> Heavy NP -> Chlorinated Paraffin -> 절삭유,압연우,난연
kerosene -> H2S -> TDM -> 고분자 분자량 중합 조절제
kerosene -> D-Sol -> 금속가공유, 인쇄잉크,PVC
kerosene -> 등유 -> 항공연료
Aceton / H2 -> IPA -> 페인트,의약품,방부제, 부동액 및 동결빙결 방지제 / 반도체,LCD 세정제
How to Fix "Cannot Find Central Directory" Error in Realme Flash Tool
If you are trying to unbrick your Realme smartphone or flash a stock ROM and encountered the "Cannot find central directory" error, you aren't alone. This specific error typically halts the flashing process before it even begins, leaving your device in limbo.
The "Central Directory" is a specific structure at the end of a ZIP file that tells software where files are located within the archive. When the Realme Flash Tool throws this error, it means it cannot read the structure of your firmware package.
Here is a comprehensive guide to fixing this issue and getting your flash back on track. 1. Check for File Corruption (The Most Common Cause)
The most frequent reason for this error is a partial or corrupted download. If the firmware (.ofp or .zip) didn't download completely, the "Central Directory" header will be missing or broken.
The Fix: Redownload the firmware from an official or trusted source. Use a download manager to ensure the connection doesn't drop mid-way.
Verify MD5: If provided, check the MD5 checksum of your downloaded file against the source to ensure they match perfectly. 2. Avoid Long File Paths and Special Characters
Windows often struggles with "Deep Paths." If your firmware is buried inside five subfolders or has a name with spaces and symbols, the Flash Tool might fail to parse the directory.
The Fix: Move your firmware file and the Flash Tool to the root of your C: drive (e.g., C:\Realme_Flash\).
Rename: Rename the firmware file to something simple like update.zip or firmware.ofp. Avoid spaces, dots (except for the extension), or emojis in the folder names. 3. Update or Change Your Extraction Tool
If you are trying to extract a compressed firmware file before loading it into the tool, the way the file was zipped matters. If you used a native Windows "Extract All" and it failed, the directory structure might be misinterpreted.
The Fix: Use 7-Zip or WinRAR (latest versions). These tools are much more robust at handling large Android sparse chunks and complex directory headers than the default Windows Explorer. 4. Use the Correct Version of Realme Flash Tool
Not all Realme Flash Tools are created equal. Older versions of the tool may not support the newer compression formats used in the latest Realme UI updates.
The Fix: Ensure you are using the official Realme Flash Tool (often version 1.0 or 2.0 depending on your model). If you are using a patched or "cracked" version of the Oppo/Realme Download Tool, try switching to the official, model-specific version. 5. Check "Run as Administrator" cannot find central directory realme flash tool fixed
The Flash Tool needs deep system access to read large files and interact with COM ports. Without proper permissions, Windows may block the tool from reading the "Central Directory" of the file.
The Fix: Right-click the Realme Flash Tool executable (.exe) and select "Run as Administrator." Quick Summary Checklist: Redownload the firmware (it’s likely corrupted). Move the files to C:\ to shorten the path. Extract using 7-Zip instead of Windows Explorer.
Disable Antivirus temporarily, as it may interfere with the tool reading the file headers.
By following these steps, the "Cannot find central directory" error should disappear, allowing you to proceed with the flashing process safely.
The Frustrating Error
Rahul, a tech enthusiast, was trying to flash a new ROM on his Realme 5 Pro using the Realme Flash Tool. He had downloaded the tool and the ROM file, and was following the instructions to the letter. However, as he reached the step where the tool was supposed to detect the phone and start the flashing process, he was greeted with a frustrating error message: "Cannot find central directory".
Rahul tried restarting the tool, re-downloading the ROM file, and even reinstalling the tool itself, but nothing seemed to work. He searched online for solutions, but all he could find were scattered forum posts and YouTube videos that didn't provide a clear fix.
The Solution
Days went by, and Rahul's phone remained stuck on the old ROM. He was on the verge of giving up when he stumbled upon a post on a Realme enthusiasts' group on Facebook. A user named "techguy" claimed to have fixed the same error by following a specific set of steps.
Desperate for a solution, Rahul decided to try techguy's method. Here's what he did:
The Fix
With a mix of skepticism and hope, Rahul followed techguy's steps. To his surprise, the Realme Flash Tool detected his phone and started the flashing process without any errors. The tool successfully flashed the new ROM, and Rahul's phone rebooted into the new software.
The Takeaway
Rahul was thrilled to have fixed the "cannot find central directory" error and upgraded his phone to the latest ROM. He realized that sometimes, a combination of simple steps can resolve seemingly complex issues. He thanked techguy for the solution and made sure to share the fix with others in the Realme enthusiasts' group.
If you're facing the same error, try Rahul's solution:
By following these steps, you might just fix the "cannot find central directory" error and successfully flash your Realme device.
To fix the "Cannot find central directory" error in the Realme Flash Tool,
you generally need to switch to an alternative tool that supports dynamic partitions
, as the official Realme Flash Tool often fails to recognize them. This error typically occurs when the tool tries to read a firmware package that is either corrupted, incompatible with your specific model, or formatted in a way the tool cannot parse. Primary Solution: Use OppoRealme Flash OFP Tool Experts from recommend using the OppoRealme Flash OFP Tool instead of the official Realme executable. Preparation : Force your Realme device into Fastboot Mode
(usually by holding Power + Volume Down) and connect it to your PC via a USB cable. Download Tool OppoRealme Flash OFP Tool and extract it on your computer. Firmware Placement : Place your downloaded OFP firmware file directly inside the extracted tool folder.
: Launch the tool's EXE file, select your region, and begin.
file shows an error or takes nearly an hour, ignore the error and continue to the next step. Slot Activation : Once finished, use the command line to execute fastboot set_active other followed by fastboot reboot to boot into the OS. Troubleshooting the "Central Directory" Error
If you prefer to continue using the official tool, check these common points of failure: Firmware Compatibility
: The "Central directory not found" message often means you are attempting to flash an OFP package not designed for your specific Realme model. Double-check that your exact model (e.g., Realme X2 vs. X2 Pro) matches the firmware. Corrupted Downloads
: This error is a standard "ZIP error" indicating the file is truncated or corrupted. Re-download the firmware, ideally using a different browser (e.g., switch from Chrome to Edge) to ensure a complete file. Driver Issues
: Ensure you have the correct USB drivers installed. You can often install these directly through the tab within the Realme Flash Tool. Bootloader Status How to Fix "Cannot Find Central Directory" Error
: Verify that your bootloader is officially unlocked, as the tool will not flash firmware on a locked device. Summary of Alternatives
The Realme Flash Tool is often a repurposed Qualcomm tool that behaves unreliably on Windows 10 or 11, especially when reading large archives.
Solution:
RealmeFlashTool.exe.To understand the fix, you must understand the problem. The "central directory" is a critical metadata header located at the end of a ZIP-based file (like .ozip or .ofp). Think of it as the index or table of contents for the entire firmware archive.
When the Realme Flash Tool looks for this directory and cannot find it, it essentially means:
In short: The flasher cannot read the map of the firmware, so it refuses to flash.
To resolve this issue, follow the steps below in order.
Inside the extracted firmware folder, ensure these exist:
META-INF\com\google\android\update-binarypayload.bin or individual .img filesflash_all.bat or flash.batIf missing → your extraction failed. Re-extract using a different OFP extractor (try Fastboot Enhance or Python ofp_extractor).
If the central directory is truly missing, you can manually extract the OFP file using a special extractor and then repack it or load the extracted files directly.
You will need: OFP Extractor Tool (Download from XDA-Developers).
Steps:
.ofp file.boot.img, system.img, vendor.img, etc.